Hardenize Report: skiff.com

Web Security Overview

HTTPS

Web sites need to use encryption to help their visitors know they're in the right place, as well as provide confidentiality and content integrity. Sites that don't support HTTPS may expose sensitive data and have their pages modified and subverted.

For all sites VERY IMPORTANT medium EFFORT

HTTPS Redirection

To deploy HTTPS properly, web sites must redirect all unsafe (plaintext) traffic to the encrypted variant. This approach ensures that no sensitive data is exposed and that further security technologies can be activated.

For all sites VERY IMPORTANT low EFFORT

HTTP Strict Transport Security

HTTP Strict Transport Security (HSTS) is an HTTPS extension that instructs browsers to remember sites that use encryption and enforce strict security requirements. Without HSTS, active network attacks are easy to carry out.

For important sites VERY IMPORTANT medium EFFORT

HSTS Preloaded

HSTS Preloading is informing browsers in advance about a site's use of HSTS, which means that strict security can be enforced even on the first visit. This approach provides best HTTPS security available today.

For important sites VERY IMPORTANT medium EFFORT

Content Security Policy

Content Security Policy (CSP) is an additional security layer that enables web sites to control browser behavior, creating a safety net that can counter attacks such as cross-site scripting.

For important sites IMPORTANT high EFFORT

Email Security Overview

No SMTP servers

This host doesn't specify any SMTP servers, which probably means that it doesn't receive email. We are unable to evaluate STARTTLS support, TLS, X.509, and DANE configuration.

DNS Zone

The global DNS infrastructure is organized as a series of hierarchical DNS zones. The root zone hosts a number of global and country TLDs, which in turn host further zones that are delegated to their customers. Each organization that controls a zone can delegate parts of its namespace to other zones. In this test we perform detailed inspection of a DNS zone, but only if the host being tested matches the zone.

Test passed

Everything seems to be well configured. Well done.

Nameserver Names

Nameservers can be referred to by name and by address. In this section we show the names, which can appear in the NS records, the referrals from the parent zone, and the SOA record. In some situations, servers from the parent zone respond authoritatively, in which case we will include them in the list as well.

Nameserver	Operational	IPv4	IPv6	Sources
heidi.ns.cloudflare.com. PRIMARY 108.162.194.236 162.159.38.236 172.64.34.236 2606:4700:50::a29f:26ec 2803:f800:50::6ca2:c2ec 2a06:98c1:50::ac40:22ec				REFERRAL NS SOA
yevgen.ns.cloudflare.com. 108.162.195.223 162.159.44.223 172.64.35.223 2606:4700:58::a29f:2cdf 2803:f800:50::6ca2:c3df 2a06:98c1:50::ac40:23df				REFERRAL NS

Nameserver Addresses

This section shows the configuration of all discovered nameservers by their IP address. To find all applicable nameservers, we inspect the parent zone nameservers for names and glue and then the tested zone nameservers for NS records. We then resolve all discovered names to IP addresses. Finally, we test each address individually.

Nameserver	Sources	Payload Size
108.162.194.236 PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
108.162.195.223 yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232
162.159.38.236 PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
162.159.44.223 yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232
172.64.34.236 PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
172.64.35.223 yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232
2606:4700:50::a29f:26ec PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
2606:4700:58::a29f:2cdf yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232
2803:f800:50::6ca2:c2ec PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
2803:f800:50::6ca2:c3df yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232
2a06:98c1:50::ac40:22ec PRIMARY heidi.ns.cloudflare.com. PTR: heidi.ns.cloudflare.com.	NAME, GLUE	1232
2a06:98c1:50::ac40:23df yevgen.ns.cloudflare.com. PTR: yevgen.ns.cloudflare.com.	NAME, GLUE	1232

Start of Authority (SOA) Record

Start of Authority (SOA) records contain administrative information pertaining to one DNS zone, especially the configuration that's used for zone transfers between the primary nameserver and the secondaries. Only one SOA record should exist, with all nameservers providing the same information.

The domain name of the primary nameserver for the zone. Also known as MNAME.Primary nameserver	heidi.ns.cloudflare.com.
Email address of the persons responsible for this zone. Also known as RNAME.Admin email	dns.cloudflare.com.
Zone serial or version number.Serial number	-1923553856
The length of time secondary nameservers should wait before querying the primary for changes.Refresh interval	10,000 seconds (about 2 hours 46 minutes)
The length of time secondary nameservers should wait before querying an unresponsive primary again.Retry interval	2,400 seconds (about 40 minutes)
The length of time after which secondary nameservers should stop responding to queries for a zone, assuming no updates were obtained from the primary.Expire interval	604,800 seconds (about 7 days)
TTL for purposes of negative response caching. Negative cache TTL	1,800 seconds (about 30 minutes)
Time To Live (TTL) indicates for how long a record remains valid. SOA record TTL	1,800 seconds (about 30 minutes)

Analysis

No problems detected with the zone configuration

Excellent. This DNS zone is in a good working order. No problems detected.

Backing DNS Queries

Below are all DNS queries we submitted during the zone inspection.

	ID	Server	Transport	Question Name	Type	Status

DNS Records

Correctly functioning name servers are necessary to hold and distribute information that's necessary for your domain name to operate correctly. Examples include converting names to IP addresses, determining where email should go, and so on. More recently, the DNS is being used to communicate email and other security policies.

Test passed

Everything seems to be well configured. Well done.

DNS Records

These are the results of individual DNS queries against your nameserver for common resource record types.

Name	TTL	Type	Data
skiff.com.	300	A	172.66.43.162
skiff.com.	300	A	172.66.40.94
www.skiff.com.	300	A	172.66.40.94
www.skiff.com.	300	A	172.66.43.162
skiff.com.	300	AAAA	2606:4700:3108:0:0:0:ac42:2ba2
skiff.com.	300	AAAA	2606:4700:3108:0:0:0:ac42:285e
www.skiff.com.	300	AAAA	2606:4700:3108:0:0:0:ac42:2ba2
www.skiff.com.	300	AAAA	2606:4700:3108:0:0:0:ac42:285e
skiff.com.	300	CAA	0 iodef "mailto:security@skiff.org"
skiff.com.	300	CAA	0 issue "amazon.com"
skiff.com.	300	CAA	0 issue "letsencrypt.org"
skiff.com.	3600	DNSKEY	257 3 13 mdsswUyr3DPW132mOi8V9xESWE8jTo0dxCjjnopKl+GqJxpVXckHAeF+KkxLbxILfDLUT0rAK9iUzy1L53eKGQ==
skiff.com.	3600	DNSKEY	256 3 13 oJMRESz5E4gYzS/q6XDrvU1qMPYIjCWzJaOau8XNEZeqCYKD5ar0IRd8KqXXFJkqmVfRvMGPmM1x8fGAa2XhSA==
skiff.com.	86400	NS	heidi.ns.cloudflare.com.
skiff.com.	86400	NS	yevgen.ns.cloudflare.com.
skiff.com.	1800	SOA	heidi.ns.cloudflare.com. dns.cloudflare.com. 2371413440 10000 2400 604800 1800
skiff.com.	60	TXT	"google-site-verification=cFZeODTSuzK_Uf5hsbkK-4Lf6yowQILKcBgM-sePmRY"
skiff.com.	60	TXT	"v=spf1 ip4:34.223.139.255 ip4:52.33.229.188 ip4:52.27.131.180 ip4:44.233.0.116 ip4:35.82.207.188 ip4:35.166.143.94 ip4:204.122.17.4/30 -all"
skiff.com.	60	TXT	"<03.15.2023>"
skiff.com.	60	TXT	"IR-a9c30691a111329d3b4a129ef44357e0ce6cfeffad73d9fcb68fd7ea6265a363"
skiff.com.	60	TXT	"MS=ms46306238"
skiff.com.	60	TXT	"MS=ms76043800"
skiff.com.	60	TXT	"MS=ms81723164"
skiff.com.	60	TXT	"ca3-dbb30cfd8fa64b0daec218ba57140e5b"
skiff.com.	60	TXT	"google-site-verification=4STeRgj8YkMzj__BsCqeIy08lfo83rGyzYwpcxREW3s"
skiff.com.	60	TXT	"google-site-verification=BKa9NWFnlHAivSYuEKaIzWni7qjFiVlBNHWqOHN-UxQ"
skiff.com.	60	TXT	"google-site-verification=CL9hOZcRvcPB3MbzIXK0lM5inm88rQzeKIwAj5u673g"
_dmarc.skiff.com.	300	TXT	"v=DMARC1;p=reject;pct=100;adkim=s;aspf=r;rua=mailto:rua-com@skiff.org,mailto:re+b36bf17d2996@inbound.dmarcdigests.com;ruf=mailto:ruf-com@skiff.org;fo=1;"
_mta-sts.skiff.com.	300	TXT	"v=STSv1; id=202305220217"
_smtp._tls.skiff.com.	300	TXT	"v=TLSRPTv1; rua=https://tlsrpt.skiff.com"

Backing DNS Queries

Below are all DNS queries we submitted while inspecting the resource records.

	ID	Server	Question Name	Type	Status

DNSSEC

DNSSEC is an extension of the DNS protocol that provides cryptographic assurance of the authenticity and integrity of responses; it's intended as a defense against network attackers who are able to manipulate DNS to redirect their victims to servers of their choice. DNSSEC is controversial, with the industry split largely between those who think it's essential and those who believe that it's problematic and unnecessary.

Test passed

Everything seems to be well configured. Well done.

Analysis

DNSSEC is well configured

Good. This domain name has well-configured DNSSEC.

Useful DNSSEC Tools

Certification Authority Authorization

CAA (RFC 8659) is a new standard that allows domain name owners to restrict which CAs are allowed to issue certificates for their domains. This can help to reduce the chance of misissuance, either accidentally or maliciously. In September 2017, CAA became mandatory for CAs to implement.

Test passed

Everything seems to be well configured. Well done.

CAA Policy Information

The DNS hostname where this policy is located.Policy host	skiff.com
The issue property tag is used to request that certificate issuers perform CAA issue restriction processing for the domain and to grant authorization to specific certificate issuers.issue	letsencrypt.org flags: 0
The issue property tag is used to request that certificate issuers perform CAA issue restriction processing for the domain and to grant authorization to specific certificate issuers.issue	amazon.com flags: 0
The iodef property specifies a means of reporting certificate issue requests or cases of certificate issue for the corresponding domain that violate the security policy of the issuer or the domain name holder.iodef	mailto:security@skiff.org flags: 0

Analysis

Issuance of S/MIME certificates not restricted

This policy doesn't restrict the issuance of S/MIME certificates. Consider using the `issuemail` directive to restrict which CAs, if any, can issue.

Issuance of BIMI not restricted

This policy doesn't restrict issuance of BIMI certificates. Consider using the `issuevmc` directive to restrict which CAs, if any, can issue.

CAA policy restricts issuance

Great. This domain name uses CAA to restrict which CAs are allowed to issue certificates for it.

Policy uses reporting

Good. This policy uses reporting, which means that your contact information is available should someone need to contact you about a CAA violation. Do note that you're not guaranteed to be notified, given that CAs generally don't support notifications yet.

Email (SMTP)

An internet hostname can be served by zero or more mail servers, as specified by MX (mail exchange) DNS resource records. Each server can further resolve to multiple IP addresses, for example to handle IPv4 and IPv6 clients. Thus, in practice, hosts that wish to receive email reliably are supported by many endpoint.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Analysis

Email servers match MTA-STS policy

Good. This host supports MTA-STS, which means that it restricts which MX servers can be used and how they are configured. We've verified that all MX servers listed here match the policy.

This host doesn't have any MX servers and doesn't receive its own email

This host doesn't specify any MX servers. According to the SMTP specification, in that case it should be assumed that the host itself is willing to receive email. We have checked and that's not the case. This host should probably deploy a NULL MX (RFC 7505) to indicate that email is not wanted, but in practice it doesn't matter a great deal.

Email TLS (SMTP)

Transport Layer Security (TLS) is the most widely used encryption protocol on the Internet. In combination with valid certificates, servers can establish trusted communication channels even with users who have never visited them before. Network attackers can't uncover what is being communicated, even when they can see all the traffic.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Email Certificates (SMTP)

A certificate is a digital document that contains a public key, some information about the entity associated with it, and a digital signature from the certificate issuer. It’s a mechanism that enables us to exchange, store, and use public keys. Being able to reliably verify the identity of a remote server is crucial in order to achieve secure encrypted communication.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Email DANE (SMTP)

DNS-based Authentication of Named Entities (DANE) is a bridge between DNSSEC and TLS. In one possible scenario, DANE can be used for public key pinning, building on an existing publicly-trusted certificate. In another approach, it can be used to completely bypass the CA ecosystem and establish trust using DNSSEC alone.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

SPF

Sender Policy Framework (SPF) is a protocol that allows domain name owners to control which internet hosts are allowed to send email on their behalf. This simple mechanism can be used to reduce the effect of email spoofing and cut down on spam.

Test passed

Everything seems to be well configured. Well done.

SPF Policy Information Main policy

Host where this policy is located.Location	skiff.com
SPF version used by this policy.v	spf1
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	34.223.139.255
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	52.33.229.188
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	52.27.131.180
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	44.233.0.116
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	35.82.207.188
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	35.166.143.94
This mechanism tests whether the IP address being tested is contained within a given IPv4 network. ip4	204.122.17.4/30
This policy element always matches. It's normally used at the end of a policy to specify the handling of hosts that don't match earlier mechanisms. -all

Analysis

SPF policy found

Policy text: v=spf1 ip4:34.223.139.255 ip4:52.33.229.188 ip4:52.27.131.180 ip4:44.233.0.116 ip4:35.82.207.188 ip4:35.166.143.94 ip4:204.122.17.4/30 -all

Location: skiff.com

SPF policy is valid

Good. Your SPF policy is syntactically valid.

Policy uses default fail

Excellent. This policy fails hosts that are not allowed to send email for this domain name.

Policy DNS lookups under limit

Good. Your policy stays under the limit of up to 10 DNS queries. The SPF specification Section 4.6.4. requires implementations to limit the total number of DNS queries. Policies that exceed the limit should not be used and may not work in practice.

Lookups: 0

DMARC

Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a scalable mechanism by which a mail-originating organization can express domain-level policies and preferences for message validation, disposition, and reporting, that a mail-receiving organization can use to improve mail handling.

Test passed

Everything seems to be well configured. Well done.

DMARC Policy Information

The location from which we obtained this policy.Policy location	_dmarc.skiff.com
DMARC version used by this policy.v	DMARC1
Indicates the policy to be enacted by the receiver at the request of the domain owner. Possible values are: none, quarantine, and reject.p	reject
Percentage of messages from mail stream to which the DMARC policy is to be applied.pct	100
Indicates whether strict or relaxed DKIM alignment mode is required.adkim	s
Indicates whether strict or relaxed SPF alignment mode is required.aspf	r
Addresses to which aggregate feedback is to be sent.rua	mailto:rua-com@skiff.org,mailto:re+b36bf17d2996@inbound.dmarcdigests.com
Addresses to which message-specific failure information is to be reported.ruf	mailto:ruf-com@skiff.org
Configures failure reporting.fo	1

Analysis

DMARC policy found

Policy: v=DMARC1;p=reject;pct=100;adkim=s;aspf=r;rua=mailto:rua-com@skiff.org,mailto:re+b36bf17d2996@inbound.dmarcdigests.com;ruf=mailto:ruf-com@skiff.org;fo=1;

Host: _dmarc.skiff.com

Valid external destination

Permission record location: skiff.com._report._dmarc.skiff.org

External destination: mailto:rua-com@skiff.org

Permission record contents: v=DMARC1

Valid external destination

Permission record location: skiff.com._report._dmarc.inbound.dmarcdigests.com

External destination: mailto:re+b36bf17d2996@inbound.dmarcdigests.com

Permission record contents: v=DMARC1;

Policy is valid

Good. You have a valid DMARC policy.

MTA Strict Transport Security

SMTP Mail Transfer Agent Strict Transport Security (MTA-STS) is a mechanism enabling mail service providers to declare their ability to receive Transport Layer Security (TLS) secure SMTP connections, and to specify whether sending SMTP servers should refuse to deliver to MX hosts that do not offer TLS with a trusted server certificate.

Test passed

Everything seems to be well configured. Well done.

MTA-STS Policy Indicator

Location from which we retrieved the policy indicator.Location	_mta-sts.skiff.com
MTA-STS standard version used by this policy indicator.Version	STSv1
Unique policy identifier, whose value must change every time the underlying policy changes.ID	202305220217

Analysis

MTA-STS policy indicator valid

Good. Your MTA-STS policy indicator is valid.

MTA-STS Policy

The URL from which the policy was obtained.Location	https://mta-sts.skiff.com/.well-known/mta-sts.txt
Policy standard version.version	STSv1
Policy duration, which specifies how long the sending MTAs should remember and enforce the server policy for.max‑age	86,400 seconds (about 1 day)
Policy mode, which can be one of 'none', 'testing' and 'enforcing'. Guess which is best! :)mode	enforce
One 'mx' directive specifies one email server pattern that's allowed for this host.mx	inbound-smtp.skiff.com

Analysis

MTA-STS policy is valid

Good. Your MTA-STS policy is valid.

Policy host certificate is valid

Good. Your MTA-STS policy is delivered via a web server that has a valid publicly trusted certificate. This is a necessary condition for the policy to be recognized.

Policy HTTPS response information

Status code: 200

Length: 75 bytes

Content-Type: text/plain;charset=UTF-8

Certificate: mta-sts.skiff.com

Leaf certificate

skiff.com
Issuer: Let's Encrypt
Not Before: 14 Mar 2025 10:46:27 UTC
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Key: EC 256 bits
Signature: SHA384withECDSA
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Analysis

Strong private key

Good. The private key associated with this certificate is secure.

Strong signature algorithm

Good. This certificate uses a strong signature algorithm.

Certificate matches hostname

Good. The provided certificate matches the expected hostnames.

Certificate dates match

Good. The certificate is valid for use at this point of time.

Certificate has not been revoked

Good. This certificate has not been revoked.

Certificate satisfies Apple's CT compliance requirements

Good. This certificate satisfies Apple's CT requirements at present.

Certificate Chain

Leaf certificate

skiff.com | 29f8ec4
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Authentication: EC 256 bits (SHA384withECDSA)
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Intermediate certificate

E5 | 5dfdb3c
Not After: 12 Mar 2027 23:59:59 UTC (expires in 1 year 10 months)
Authentication: EC 384 bits (SHA256withRSA)
View details

Subject DN	CN=E5, O=Let's Encrypt, C=US
Subject Key Identifier	9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Serial	838f6c63ceb1398c6206628315c9fdde
Not Before	13 Mar 2024 00:00:00 UTC
Not After	12 Mar 2027 23:59:59 UTC
Validity period	1095 days
Key Usage	digitalSignature, keyCertSign, cRLSign
Extended Key Usage	clientAuth, serverAuth
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Not Applicable
Authority Key Identifier	keyid:79b459e67bb6e5e40173800888c81a58f6e99b6e
Parent Certificate	http://x1.i.lencr.org/
CRL	http://x1.c.lencr.org/
CA certificate	Yes (pathlen 0)
Fingerprints
SHA1	5f28d9c589ee4bf31a11b78c72b8d13f079ddc45
SHA256	5dfdb3cf31b26f23d87c09f3a0cef642f64069a9fb7cfe29270bb5dc0f1e16bb
SPKI SHA256	3586d4ecf070578cbd27aedce20b964e48bc149faeb9dad72f46b857869172b8

Root certificate

ISRG Root X1 | 96bcec0
Not After: 04 Jun 2035 11:04:38 UTC (expires in 10 years 28 days)
Authentication: RSA 4096 bits (SHA256withRSA)
View details

Subject DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Subject Key Identifier	79b459e67bb6e5e40173800888c81a58f6e99b6e
Serial	8210cfb0d240e3594463e0bb63828b00
Not Before	04 Jun 2015 11:04:38 UTC
Not After	04 Jun 2035 11:04:38 UTC
Key Usage	keyCertSign, cRLSign
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Self-signed
CA certificate	Yes (pathlen unlimited)
Fingerprints
SHA1	cabd2a79a1076a31f21d253635cb039d4329a5e8
SHA256	96bcec06264976f37460779acf28c5a7cfe8a3c0aae11a8ffcee05c0bddf08c6
SPKI SHA256	0b9fa5a59eed715c26c1020c711b4f6ec42d58b0015e14337a39dad301c5afc3

Analysis

Certificate chain is correct

Good. This chain contains all the right certificates and in the right order.

SMTP TLS Reporting

SMTP TLS Reporting (RFC 8460), or TLS-RPT for short, describes a reporting mechanism and format by which systems sending email can share statistics and specific information about potential failures with recipient domains. Recipient domains can then use this information to both detect potential attacks and diagnose unintentional misconfigurations. TLS-RPT can be used with DANE or MTA-STS.

Test passed

Everything seems to be well configured. Well done.

TLS-RPT Policy

Location from which we retrieved the policy indicator.Location	_smtp._tls.skiff.com
TLS-RPT standard version used by this policy indicator.Version	TLSRPTv1
Reporting endpoints specified in the policy.Reporting Endpoints	https://tlsrpt.skiff.com

Analysis

SMTP TLS-RPT policy valid

Good. Your TLS-RPT policy is valid. SMTP TLS Reporting is a young standard that is not yet widely supported, but support is probably going to increase over time.

HTTP (80)

To observe your HTTP implementation, we submit a request to the homepage of your site on port 80, follow all redirections (even when they take us to other domain names), and record the returned HTTP headers.

Test passed

Everything seems to be well configured. Well done.

URL: http://skiff.com/

1

http://skiff.com/

HTTP/1.1 301 Moved Permanently

Date	Tue, 06 May 2025 20:36:14 GMT
Content-Type	text/html
Content-Length	167
Connection	keep-alive
Cache-Control	max-age=3600
Expires	Tue, 06 May 2025 21:36:14 GMT
Location	https://skiff.com/
Set-Cookie	__cf_bm=D5pHjS0Ht7seyuaHQtIPofthKCFdlM0iA8dJluke1co-1746563774-1.0.1.1-hvj3GR8PL.E3c_GsvI4FqBM9MrL0COTaHJWjPuyO9Kq.oDmb1a0cc8JCPKM3rVGTENlUu4GmCvXRCHKRCbRu6c7lWPY0HzlAxrcOvipMTeo; path=/; expires=Tue, 06-May-25 21:06:14 GMT; domain=.skiff.com; HttpOnly
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=xuSvIxeDy0fPOCKrm0VD2fKfLfT57R5bHkAWOGEIPFbwA4t8Rh9nDBwL3Iv3Oj4T27ht33ymC5btl1pL6%2BrgOj73Xlq8sAlf%2BnpyYO9VU4zGncl90fGXODF1wg%3D%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0.01,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
X-Content-Type-Options	nosniff
Server	cloudflare
CF-RAY	93bb44c86df405fd-IAD

2

https://skiff.com/

HTTP/1.1 200 OK

Date	Tue, 06 May 2025 20:36:14 GMT
Content-Type	text/html; charset=utf-8
Transfer-Encoding	chunked
Connection	keep-alive
Cache-Control	public, max-age=0, must-revalidate
content-security-policy	default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; script-src-elem 'self' 'unsafe-inline' https://platform.twitter.com/js/ https://platform.twitter.com/widgets.js https://www.youtube.com https://cdn.matomo.cloud/skiff.matomo.cloud/matomo.js https://skiff.matomo.cloud/plugins/HeatmapSessionRecording/; style-src 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com; font-src 'self' data:; frame-src 'self' https://platform.twitter.com/ https://www.youtube.com; img-src 'self' https://cdn.sanity.io https://i.ytimg.com; manifest-src 'self'; media-src 'self'; report-uri https://cspreports.skiff.com; worker-src 'self'
content-security-policy-report-only	require-trusted-types-for 'script'; report-uri https://cspreports.skiff.com
permissions-policy	accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=()
referrer-policy	strict-origin-when-cross-origin
x-content-type-options	nosniff
x-frame-options	DENY
x-xss-protection	0
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=pLMKjsE6yQT7C6YJxFgVjqONwMikSZrANW2s6kkfN0XLL8foQjOlLe85JFrOWXEmTVBiQble4pFYjOwNj8%2BvzNpJtmr2e%2F4rUL6h6%2FhZdls38wyKDnuIKMRm%2BF4%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
cf-cache-status	DYNAMIC
Strict-Transport-Security	max-age=31536000; includeSubDomains; preload
Server	cloudflare
CF-RAY	93bb44c91fcf208d-IAD

Analysis

HTTP redirects to HTTPS

Good. This plaintext HTTP server redirects to HTTPS.

URL: http://www.skiff.com/

1

http://www.skiff.com/

HTTP/1.1 301 Moved Permanently

Date	Tue, 06 May 2025 20:36:15 GMT
Content-Type	text/html
Content-Length	167
Connection	keep-alive
Cache-Control	max-age=3600
Expires	Tue, 06 May 2025 21:36:15 GMT
Location	https://skiff.com/
Set-Cookie	__cf_bm=nIflNOFLoqds8mqK1o5.eiT6OGDWnlGPh_SpLN6KbkA-1746563775-1.0.1.1-fIqfDqx8kDhCcrWirivMkW.aMoyljOFUstr1l4CKWYm_aSg7O8WbxoRnLszLf8KLAJJlqhGGSLaMwX3LccBf_DwjRlhWraJBQJFYCcTiCvc; path=/; expires=Tue, 06-May-25 21:06:15 GMT; domain=.skiff.com; HttpOnly
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=tVn3BPNHZrvysqfqaxk2RMwZnQg%2Fw63ut3gikeFYrxStk54y2phuPSKD9FCUfJr4d9PAr5StCcNzxxpryte6MOSLjNCr4M%2BUrNH7eLdAdg6WN1cgTWWnqAL1zqEpi18%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0.01,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
X-Content-Type-Options	nosniff
Server	cloudflare
CF-RAY	93bb44c9e9513925-IAD

2

https://skiff.com/

HTTP/1.1 200 OK

Date	Tue, 06 May 2025 20:36:15 GMT
Content-Type	text/html; charset=utf-8
Transfer-Encoding	chunked
Connection	keep-alive
Cache-Control	public, max-age=0, must-revalidate
content-security-policy	default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; script-src-elem 'self' 'unsafe-inline' https://platform.twitter.com/js/ https://platform.twitter.com/widgets.js https://www.youtube.com https://cdn.matomo.cloud/skiff.matomo.cloud/matomo.js https://skiff.matomo.cloud/plugins/HeatmapSessionRecording/; style-src 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com; font-src 'self' data:; frame-src 'self' https://platform.twitter.com/ https://www.youtube.com; img-src 'self' https://cdn.sanity.io https://i.ytimg.com; manifest-src 'self'; media-src 'self'; report-uri https://cspreports.skiff.com; worker-src 'self'
content-security-policy-report-only	require-trusted-types-for 'script'; report-uri https://cspreports.skiff.com
permissions-policy	accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=()
referrer-policy	strict-origin-when-cross-origin
x-content-type-options	nosniff
x-frame-options	DENY
x-xss-protection	0
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=lREer18F6RHS3Oy89R6FKE%2Bwb5w%2Fp%2F3Jjwhxz1jtfoWvgktFaB9yC2mcY%2BDygIiUOIfIgM9HzDWcSeCJce6mG%2B1O1Wge1CHWqR12%2BjiPXH%2Brc7CvNR9hzJmDtnJdbYUzpmkNL1dsT4w%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
cf-cache-status	DYNAMIC
Set-Cookie	__cf_bm=NoNDAJJBdSWAqcWM7y8t5yMWBW9hIAW52Wd8f6E1GdI-1746563775-1.0.1.1-0f4Ki5MOxvbARknhv86ym1iXvtCxHriZqxeyECcGiADyizB0YFtuapyLGMGh_jRgFhzwQFs8gr7k9qr6IWlIbAB5Gk5aq4lVusWSvNw0Je0; path=/; expires=Tue, 06-May-25 21:06:15 GMT; domain=.skiff.com; HttpOnly; Secure; SameSite=None
Strict-Transport-Security	max-age=31536000; includeSubDomains; preload
Server	cloudflare
CF-RAY	93bb44caae1559fe-IAD

Analysis

HTTP redirects to HTTPS

Good. This plaintext HTTP server redirects to HTTPS.

HTTP (443)

To observe your HTTPS implementation, we submit a request to the homepage of your site on port 443, follow all redirections (even when they take us to other domain names), and record the returned HTTP headers. We use the most recent set of headers returned from the tested hostname for further tests such as HSTS and HPKP.

Test passed

Everything seems to be well configured. Well done.

URL: https://skiff.com/

1

https://skiff.com/

HTTP/1.1 200 OK

Date	Tue, 06 May 2025 20:36:15 GMT
Content-Type	text/html; charset=utf-8
Transfer-Encoding	chunked
Connection	keep-alive
Cache-Control	public, max-age=0, must-revalidate
content-security-policy	default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; script-src-elem 'self' 'unsafe-inline' https://platform.twitter.com/js/ https://platform.twitter.com/widgets.js https://www.youtube.com https://cdn.matomo.cloud/skiff.matomo.cloud/matomo.js https://skiff.matomo.cloud/plugins/HeatmapSessionRecording/; style-src 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com; font-src 'self' data:; frame-src 'self' https://platform.twitter.com/ https://www.youtube.com; img-src 'self' https://cdn.sanity.io https://i.ytimg.com; manifest-src 'self'; media-src 'self'; report-uri https://cspreports.skiff.com; worker-src 'self'
content-security-policy-report-only	require-trusted-types-for 'script'; report-uri https://cspreports.skiff.com
permissions-policy	accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=()
referrer-policy	strict-origin-when-cross-origin
x-content-type-options	nosniff
x-frame-options	DENY
x-xss-protection	0
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=H5eUzQgDmSOykPwIxvL1FPOdagsWLj59nhQDc7IE0CVVw7TpH%2F4mwIN5pJPoaot7txj5AmtPm%2Fda5RxZaN84LALb78vnG5RjeNMz56c6ZOQjuGWbOabxYSFpuPA%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
cf-cache-status	DYNAMIC
Set-Cookie	__cf_bm=8EHbXfbn.BREFiYTTx6F8spPebtzPadlA0Boe4kAoWg-1746563775-1.0.1.1-fbpr4lF0SIWC_tE2bkfl1wPfXUQgMDsSGKiV_.ME7boCdEkuA2VHssvnaxy4Fe3RuQn3ITdfunev3jjL_nOF6jzWl4pvfMX1BhLishCjdwE; path=/; expires=Tue, 06-May-25 21:06:15 GMT; domain=.skiff.com; HttpOnly; Secure; SameSite=None
Strict-Transport-Security	max-age=31536000; includeSubDomains; preload
Server	cloudflare
CF-RAY	93bb44cbbcc12017-IAD

URL: https://www.skiff.com/

1

https://www.skiff.com/

HTTP/1.1 301 Moved Permanently

Date	Tue, 06 May 2025 20:36:15 GMT
Content-Type	text/html
Content-Length	167
Connection	keep-alive
Cache-Control	max-age=3600
Expires	Tue, 06 May 2025 21:36:15 GMT
Location	https://skiff.com/
Set-Cookie	__cf_bm=1uGzK7k.pLJT9Ga6qkV5YfT5TLgC3yPwT2Qqi31fbvo-1746563775-1.0.1.1-Mjpb5zj6NLLjcIslfPjdzxxJ.GRfrdDxf93lr1VRZlDU08ZONzCRwS7ylXdnTKofQ1qxQXZSsFhkrrRG3n8._tp8llKTHv3LOJ_3Eqy5hJs; path=/; expires=Tue, 06-May-25 21:06:15 GMT; domain=.skiff.com; HttpOnly; Secure; SameSite=None
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=bMju8BgS%2F2PJe0sWstwQ0ODA40Kcy3Gw1FCTCzmynI0E2YpnZU%2FYt7u9dwOax4dLDKKE6ridlKB%2Fqmg5EjmMHWOSxvxxdek%2BcsnOtj%2FD6bw1BuqIjABnLvoL9AzaYvs%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0.01,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
Strict-Transport-Security	max-age=31536000; includeSubDomains; preload
X-Content-Type-Options	nosniff
Server	cloudflare
CF-RAY	93bb44cd0c3f9c82-IAD

2

https://skiff.com/

HTTP/1.1 200 OK

Date	Tue, 06 May 2025 20:36:15 GMT
Content-Type	text/html; charset=utf-8
Transfer-Encoding	chunked
Connection	keep-alive
Cache-Control	public, max-age=0, must-revalidate
content-security-policy	default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; script-src-elem 'self' 'unsafe-inline' https://platform.twitter.com/js/ https://platform.twitter.com/widgets.js https://www.youtube.com https://cdn.matomo.cloud/skiff.matomo.cloud/matomo.js https://skiff.matomo.cloud/plugins/HeatmapSessionRecording/; style-src 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com; font-src 'self' data:; frame-src 'self' https://platform.twitter.com/ https://www.youtube.com; img-src 'self' https://cdn.sanity.io https://i.ytimg.com; manifest-src 'self'; media-src 'self'; report-uri https://cspreports.skiff.com; worker-src 'self'
content-security-policy-report-only	require-trusted-types-for 'script'; report-uri https://cspreports.skiff.com
permissions-policy	accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=()
referrer-policy	strict-origin-when-cross-origin
x-content-type-options	nosniff
x-frame-options	DENY
x-xss-protection	0
Report-To	{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=DTQTFaQaj%2BBV1VcghYVi0lYWcdtkmODcxaiKgGeGaIgLWAvBqUTI8ZqXVV6rTuQ4CQeaV2qQ0LGD2PeP496PIk7er%2B7RV63HFeOS%2FbVGoI6dmRVqlrwIdFFZz553DXJubuiPDn%2FlZxs%3D"}],"group":"cf-nel","max_age":604800}
NEL	{"success_fraction":0,"report_to":"cf-nel","max_age":604800}
Vary	Accept-Encoding
cf-cache-status	DYNAMIC
Set-Cookie	__cf_bm=xggFXu2Sh2_HFpx9lFcHogiQ2uodsuc.7sderYww0wc-1746563775-1.0.1.1-MZjl1U9t3JDV2EOoIBQsql0TzBY4.plhBP7WPAhy9qv95ersN4n1znsN9ztVuBJGzPqfI9HgZSclXFG8B4DEbhf065VPN.iHyq.yM8WwrEg; path=/; expires=Tue, 06-May-25 21:06:15 GMT; domain=.skiff.com; HttpOnly; Secure; SameSite=None
Strict-Transport-Security	max-age=31536000; includeSubDomains; preload
Server	cloudflare
CF-RAY	93bb44cd8ca6e5e6-IAD

WWW TLS

Transport Layer Security (TLS) is the most widely used encryption protocol on the Internet. In combination with valid certificates, servers can establish trusted communication channels even with users who have never visited them before. Network attackers can't uncover what is being communicated, even when they can see all the traffic.

Test passed

Everything seems to be well configured. Well done.

TLS Configuration: skiff.com (2606:4700:3108:0:0:0:ac42:285e)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: www.skiff.com (2606:4700:3108:0:0:0:ac42:2ba2)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: www.skiff.com (2606:4700:3108:0:0:0:ac42:285e)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: skiff.com (2606:4700:3108:0:0:0:ac42:2ba2)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: www.skiff.com (172.66.40.94)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: skiff.com (172.66.40.94)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: www.skiff.com (172.66.43.162)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

TLS Configuration: skiff.com (172.66.43.162)

Encryption protocol version determines what features are available for negotiation between client and server.Supported protocols	TLS v1.3 TLS v1.2
Servers should always enforce their own cipher suite preference, as that is the only approach that guarantees that the best possible suite is selected.Server suite preference
Shows cipher suite configuration for this protocol version.TLS v1.3 Server preference	Suite: TLS_CHACHA20_POLY1305_SHA256 Suite ID: 0x1303 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_CHACHA20_POLY1305_SHA256 256 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_128_GCM_SHA256 Suite ID: 0x1301 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA256 TLS_AES_128_GCM_SHA256 128 bits (Hybrid PQ 9472 bits) Suite: TLS_AES_256_GCM_SHA384 Suite ID: 0x1302 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: X25519MLKEM768 Key exchange strength: Hybrid PQ X25519MLKEM768 (9472 bits) Forward secrecy: Yes PRF: SHA384 TLS_AES_256_GCM_SHA384 256 bits (Hybrid PQ 9472 bits)
Shows cipher suite configuration for this protocol version.TLS v1.2 Server preference	Suite: TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca9 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02b Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA Suite ID: 0xc009 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc02c Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA Suite ID: 0xc00a Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc023 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc024 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_ECDSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 Suite ID: 0xcca8 Cipher name: CHACHA20 Cipher strength: 256 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0xc02f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite ID: 0xc013 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite ID: 0x9c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_GCM_SHA256 128 bits Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite ID: 0x2f Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_128_CBC_SHA 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0xc030 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA Suite ID: 0xc014 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_GCM_SHA384 Suite ID: 0x9d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: AEAD Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA384 TLS_RSA_WITH_AES_256_GCM_SHA384 256 bits Suite: TLS_RSA_WITH_AES_256_CBC_SHA Suite ID: 0x35 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA TLS_RSA_WITH_AES_256_CBC_SHA 256 bits Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0xc027 Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 128 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_128_CBC_SHA256 Suite ID: 0x3c Cipher name: AES Cipher strength: 128 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_128_CBC_SHA256 128 bits Suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 Suite ID: 0xc028 Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: ECDHE_RSA Key exchange strength: EC ecdh_x25519 (256 bits) Forward secrecy: Yes PRF: SHA384 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 256 bits (ECDHE 256 bits) Suite: TLS_RSA_WITH_AES_256_CBC_SHA256 Suite ID: 0x3d Cipher name: AES Cipher strength: 256 bits Cipher block size: 128 bits Cipher mode: CBC Key exchange: RSA Key exchange strength: 2048 bits Forward secrecy: No (WEAK) PRF: SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 256 bits

Analysis

TLS 1.3 supported

Excellent. This server supports TLS 1.3, which is the latest revision of the TLS protocol and a significant improvement over earlier versions. Developed over a period of several years and extensively analyzed prior to the release, TLS 1.3 removed insecure features, and improved both security and performance.

TLS 1.2 supported

Good. This server supports TLS 1.2, which can provide strong security when configured correctly. This version of the TLS protocol is necessary to provide good security with a wide range of clients that don't yet support TLS 1.3.

Deprecated protocols not supported

Excellent. This server doesn't support any of the deprecated protocol (TLS 1.1 and earlier).

Strong key exchange detected

Excellent. All cipher suites on this server rely on strong key exchange. The sweet spot is 2048 bits for DHE and 256 bits for ECDHE. Putting ECDHE suites first guarantees best security and best performance.

Server prefers forward secrecy and authenticated encryption suites

Excellent. Not only does this server enforce its server preference, but it also has at the top of the list suites that support both forward secrecy and authenticated encryption. This is the best TLS 1.2 can offer.

Server enforces cipher suite preferences

Excellent. This server enforces server cipher suite preference, which means that it is able to select the best suite from the options submitted by clients. Combined with a well-designed list of supported cipher suites, this setting enables negotiation of best security.

All TLS connections with this server satisfy Apple's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

All TLS connections with this server satisfy Chrome's CT requirements

All TLS connections established with this server satisfy Chrome's CT requirements, using certificate, TLS extension, or OCSP response as SCT transport method.

SCT transports: CERT

Post-quantum key exchange supported

Excellent. This server supports post-quantum cryptography (PQC) and uses it for key exchange. PQC is still in the process of being standardized and deployed. Protecting the key exchange against future quantum computers is considered to be one of the more pressing tasks.

Algorithm: X25519MLKEM768

DHE suites not supported

This server doesn't support the Diffie-Hellman (DH) key exchange.

WWW Certificates

A certificate is a digital document that contains a public key, some information about the entity associated with it, and a digital signature from the certificate issuer. It’s a mechanism that enables us to exchange, store, and use public keys. Being able to reliably verify the identity of a remote server is crucial in order to achieve secure encrypted communication.

Test passed

Everything seems to be well configured. Well done.

Certificate: skiff.com

Leaf certificate

skiff.com
Issuer: Let's Encrypt
Not Before: 14 Mar 2025 10:46:17 UTC
Not After: 12 Jun 2025 10:46:16 UTC (expires in 1 month 5 days)
Key: RSA 2048 bits
Signature: SHA256withRSA
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	279bb6a34800bc5cbe73960792c2f47fff243015
Serial	6405c2b7fec0ba79e74462fa732a1845e30
Not Before	14 Mar 2025 10:46:17 UTC
Not After	12 Jun 2025 10:46:16 UTC
Validity period	90 days
Key Usage	digitalSignature, keyEncipherment
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=R11, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Parent Certificate	http://r11.i.lencr.org/
CRL	http://r11.c.lencr.org/49.crl
OCSP	http://r11.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:48 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:48 UTC \| Google 'Xenon2025h1' log \| Qualified
Fingerprints
SHA1	e13a64e5cdd05e085c0d20e61a2473a694751898
SHA256	ee4bc3a18b27b873b4c9a1e67a257b52a7cf68d8cebb3b7256bf855010dbbdbc
SPKI SHA256	4ed495d9405200bdc4e9b35c52ebe4500dcfafd0733a969f01bc293027b00991

Analysis

Strong private key

Good. The private key associated with this certificate is secure.

Strong signature algorithm

Good. This certificate uses a strong signature algorithm.

Certificate matches hostname

Good. The provided certificate matches the expected hostnames.

Certificate dates match

Good. The certificate is valid for use at this point of time.

Certificate has not been revoked

Good. This certificate has not been revoked.

Certificate satisfies Apple's CT compliance requirements

Good. This certificate satisfies Apple's CT requirements at present.

Certificate Trust

Determining whether a certificate is considered valid is a complicated process that depends on the exact configuration of the validating party. For trust to be established, the certificate must form a chain that ends with a trusted root. In this section we evaluate the server's certificate against major root stores.

Platform	Trusted
Apple
Google AOSP
Microsoft
Mozilla

Certificate Chain

For a server certificate to be valid, it must be presented as part of a complete and valid certificate chain. The last certificate in the chain should be the root and is usually not included in the configuration.

Leaf certificate

skiff.com | ee4bc3a
Not After: 12 Jun 2025 10:46:16 UTC (expires in 1 month 5 days)
Authentication: RSA 2048 bits (SHA256withRSA)
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	279bb6a34800bc5cbe73960792c2f47fff243015
Serial	6405c2b7fec0ba79e74462fa732a1845e30
Not Before	14 Mar 2025 10:46:17 UTC
Not After	12 Jun 2025 10:46:16 UTC
Validity period	90 days
Key Usage	digitalSignature, keyEncipherment
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=R11, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Parent Certificate	http://r11.i.lencr.org/
CRL	http://r11.c.lencr.org/49.crl
OCSP	http://r11.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:48 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:48 UTC \| Google 'Xenon2025h1' log \| Qualified
Fingerprints
SHA1	e13a64e5cdd05e085c0d20e61a2473a694751898
SHA256	ee4bc3a18b27b873b4c9a1e67a257b52a7cf68d8cebb3b7256bf855010dbbdbc
SPKI SHA256	4ed495d9405200bdc4e9b35c52ebe4500dcfafd0733a969f01bc293027b00991

Intermediate certificate

R11 | 591e9ce
Not After: 12 Mar 2027 23:59:59 UTC (expires in 1 year 10 months)
Authentication: RSA 2048 bits (SHA256withRSA)
View details

Subject DN	CN=R11, O=Let's Encrypt, C=US
Subject Key Identifier	c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Serial	8a7d3e13d62f30ef2386bd29076b34f8
Not Before	13 Mar 2024 00:00:00 UTC
Not After	12 Mar 2027 23:59:59 UTC
Validity period	1095 days
Key Usage	digitalSignature, keyCertSign, cRLSign
Extended Key Usage	clientAuth, serverAuth
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Not Applicable
Authority Key Identifier	keyid:79b459e67bb6e5e40173800888c81a58f6e99b6e
Parent Certificate	http://x1.i.lencr.org/
CRL	http://x1.c.lencr.org/
CA certificate	Yes (pathlen 0)
Fingerprints
SHA1	696db3af0dffc17e65c6a20d925c5a7bd24dec7e
SHA256	591e9ce6c863d3a079e9fabe1478c7339a26b21269dde795211361024ae31a44
SPKI SHA256	6ddac18698f7f1f7e1c69b9bce420d974ac6f94ca8b2c761701623f99c767dc7

Root certificate

ISRG Root X1 | 96bcec0
Not After: 04 Jun 2035 11:04:38 UTC (expires in 10 years 28 days)
Authentication: RSA 4096 bits (SHA256withRSA)
View details

Subject DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Subject Key Identifier	79b459e67bb6e5e40173800888c81a58f6e99b6e
Serial	8210cfb0d240e3594463e0bb63828b00
Not Before	04 Jun 2015 11:04:38 UTC
Not After	04 Jun 2035 11:04:38 UTC
Key Usage	keyCertSign, cRLSign
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Self-signed
CA certificate	Yes (pathlen unlimited)
Fingerprints
SHA1	cabd2a79a1076a31f21d253635cb039d4329a5e8
SHA256	96bcec06264976f37460779acf28c5a7cfe8a3c0aae11a8ffcee05c0bddf08c6
SPKI SHA256	0b9fa5a59eed715c26c1020c711b4f6ec42d58b0015e14337a39dad301c5afc3

Analysis

Certificate chain is correct

Good. This chain contains all the right certificates and in the right order.

Certificate: www.skiff.com

Leaf certificate

skiff.com
Issuer: Let's Encrypt
Not Before: 14 Mar 2025 10:46:27 UTC
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Key: EC 256 bits
Signature: SHA384withECDSA
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Analysis

Strong private key

Good. The private key associated with this certificate is secure.

Strong signature algorithm

Good. This certificate uses a strong signature algorithm.

Certificate matches hostname

Good. The provided certificate matches the expected hostnames.

Certificate dates match

Good. The certificate is valid for use at this point of time.

Certificate has not been revoked

Good. This certificate has not been revoked.

Certificate satisfies Apple's CT compliance requirements

Good. This certificate satisfies Apple's CT requirements at present.

Certificate Trust

Determining whether a certificate is considered valid is a complicated process that depends on the exact configuration of the validating party. For trust to be established, the certificate must form a chain that ends with a trusted root. In this section we evaluate the server's certificate against major root stores.

Platform	Trusted
Apple
Google AOSP
Microsoft
Mozilla

Certificate Chain

For a server certificate to be valid, it must be presented as part of a complete and valid certificate chain. The last certificate in the chain should be the root and is usually not included in the configuration.

Leaf certificate

skiff.com | 29f8ec4
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Authentication: EC 256 bits (SHA384withECDSA)
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Intermediate certificate

E5 | 5dfdb3c
Not After: 12 Mar 2027 23:59:59 UTC (expires in 1 year 10 months)
Authentication: EC 384 bits (SHA256withRSA)
View details

Subject DN	CN=E5, O=Let's Encrypt, C=US
Subject Key Identifier	9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Serial	838f6c63ceb1398c6206628315c9fdde
Not Before	13 Mar 2024 00:00:00 UTC
Not After	12 Mar 2027 23:59:59 UTC
Validity period	1095 days
Key Usage	digitalSignature, keyCertSign, cRLSign
Extended Key Usage	clientAuth, serverAuth
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Not Applicable
Authority Key Identifier	keyid:79b459e67bb6e5e40173800888c81a58f6e99b6e
Parent Certificate	http://x1.i.lencr.org/
CRL	http://x1.c.lencr.org/
CA certificate	Yes (pathlen 0)
Fingerprints
SHA1	5f28d9c589ee4bf31a11b78c72b8d13f079ddc45
SHA256	5dfdb3cf31b26f23d87c09f3a0cef642f64069a9fb7cfe29270bb5dc0f1e16bb
SPKI SHA256	3586d4ecf070578cbd27aedce20b964e48bc149faeb9dad72f46b857869172b8

Root certificate

ISRG Root X1 | 96bcec0
Not After: 04 Jun 2035 11:04:38 UTC (expires in 10 years 28 days)
Authentication: RSA 4096 bits (SHA256withRSA)
View details

Subject DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Subject Key Identifier	79b459e67bb6e5e40173800888c81a58f6e99b6e
Serial	8210cfb0d240e3594463e0bb63828b00
Not Before	04 Jun 2015 11:04:38 UTC
Not After	04 Jun 2035 11:04:38 UTC
Key Usage	keyCertSign, cRLSign
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Self-signed
CA certificate	Yes (pathlen unlimited)
Fingerprints
SHA1	cabd2a79a1076a31f21d253635cb039d4329a5e8
SHA256	96bcec06264976f37460779acf28c5a7cfe8a3c0aae11a8ffcee05c0bddf08c6
SPKI SHA256	0b9fa5a59eed715c26c1020c711b4f6ec42d58b0015e14337a39dad301c5afc3

Analysis

Certificate chain is correct

Good. This chain contains all the right certificates and in the right order.

Certificate: skiff.com

Leaf certificate

skiff.com
Issuer: Let's Encrypt
Not Before: 14 Mar 2025 10:46:27 UTC
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Key: EC 256 bits
Signature: SHA384withECDSA
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Analysis

Strong private key

Good. The private key associated with this certificate is secure.

Strong signature algorithm

Good. This certificate uses a strong signature algorithm.

Certificate matches hostname

Good. The provided certificate matches the expected hostnames.

Certificate dates match

Good. The certificate is valid for use at this point of time.

Certificate has not been revoked

Good. This certificate has not been revoked.

Certificate satisfies Apple's CT compliance requirements

Good. This certificate satisfies Apple's CT requirements at present.

Certificate Trust

Determining whether a certificate is considered valid is a complicated process that depends on the exact configuration of the validating party. For trust to be established, the certificate must form a chain that ends with a trusted root. In this section we evaluate the server's certificate against major root stores.

Platform	Trusted
Apple
Google AOSP
Microsoft
Mozilla

Certificate Chain

For a server certificate to be valid, it must be presented as part of a complete and valid certificate chain. The last certificate in the chain should be the root and is usually not included in the configuration.

Leaf certificate

skiff.com | 29f8ec4
Not After: 12 Jun 2025 10:46:26 UTC (expires in 1 month 5 days)
Authentication: EC 256 bits (SHA384withECDSA)
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	f53ee62051f74c271373603db6c35dd229fd8b1f
Serial	6d197c86c531822fdff11ffe715c4cbf7e2
Not Before	14 Mar 2025 10:46:27 UTC
Not After	12 Jun 2025 10:46:26 UTC
Validity period	90 days
Key Usage	digitalSignature
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=E5, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Parent Certificate	http://e5.i.lencr.org/
CRL	http://e5.c.lencr.org/99.crl
OCSP	http://e5.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:57 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:57 UTC \| Google 'Argon2025h1' log \| Qualified
Fingerprints
SHA1	e6f1d95f690510310dcbe09f1122a299f0d1be19
SHA256	29f8ec4a8ef3863f64790e31b4a7971a7e8688ab9ffbeebc4a806e8dc4a1265f
SPKI SHA256	c79864dc21f9357cf822089fdc59b0e21c315f53f454eb35bb648a5d43f91452

Intermediate certificate

E5 | 5dfdb3c
Not After: 12 Mar 2027 23:59:59 UTC (expires in 1 year 10 months)
Authentication: EC 384 bits (SHA256withRSA)
View details

Subject DN	CN=E5, O=Let's Encrypt, C=US
Subject Key Identifier	9f2b5fcf3c214f9d04b7ed2b2cc4c6708bd2d70d
Serial	838f6c63ceb1398c6206628315c9fdde
Not Before	13 Mar 2024 00:00:00 UTC
Not After	12 Mar 2027 23:59:59 UTC
Validity period	1095 days
Key Usage	digitalSignature, keyCertSign, cRLSign
Extended Key Usage	clientAuth, serverAuth
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Not Applicable
Authority Key Identifier	keyid:79b459e67bb6e5e40173800888c81a58f6e99b6e
Parent Certificate	http://x1.i.lencr.org/
CRL	http://x1.c.lencr.org/
CA certificate	Yes (pathlen 0)
Fingerprints
SHA1	5f28d9c589ee4bf31a11b78c72b8d13f079ddc45
SHA256	5dfdb3cf31b26f23d87c09f3a0cef642f64069a9fb7cfe29270bb5dc0f1e16bb
SPKI SHA256	3586d4ecf070578cbd27aedce20b964e48bc149faeb9dad72f46b857869172b8

Root certificate

ISRG Root X1 | 96bcec0
Not After: 04 Jun 2035 11:04:38 UTC (expires in 10 years 28 days)
Authentication: RSA 4096 bits (SHA256withRSA)
View details

Subject DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Subject Key Identifier	79b459e67bb6e5e40173800888c81a58f6e99b6e
Serial	8210cfb0d240e3594463e0bb63828b00
Not Before	04 Jun 2015 11:04:38 UTC
Not After	04 Jun 2035 11:04:38 UTC
Key Usage	keyCertSign, cRLSign
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Self-signed
CA certificate	Yes (pathlen unlimited)
Fingerprints
SHA1	cabd2a79a1076a31f21d253635cb039d4329a5e8
SHA256	96bcec06264976f37460779acf28c5a7cfe8a3c0aae11a8ffcee05c0bddf08c6
SPKI SHA256	0b9fa5a59eed715c26c1020c711b4f6ec42d58b0015e14337a39dad301c5afc3

Analysis

Certificate chain is correct

Good. This chain contains all the right certificates and in the right order.

Certificate: www.skiff.com

Leaf certificate

skiff.com
Issuer: Let's Encrypt
Not Before: 14 Mar 2025 10:46:17 UTC
Not After: 12 Jun 2025 10:46:16 UTC (expires in 1 month 5 days)
Key: RSA 2048 bits
Signature: SHA256withRSA
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	279bb6a34800bc5cbe73960792c2f47fff243015
Serial	6405c2b7fec0ba79e74462fa732a1845e30
Not Before	14 Mar 2025 10:46:17 UTC
Not After	12 Jun 2025 10:46:16 UTC
Validity period	90 days
Key Usage	digitalSignature, keyEncipherment
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=R11, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Parent Certificate	http://r11.i.lencr.org/
CRL	http://r11.c.lencr.org/49.crl
OCSP	http://r11.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:48 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:48 UTC \| Google 'Xenon2025h1' log \| Qualified
Fingerprints
SHA1	e13a64e5cdd05e085c0d20e61a2473a694751898
SHA256	ee4bc3a18b27b873b4c9a1e67a257b52a7cf68d8cebb3b7256bf855010dbbdbc
SPKI SHA256	4ed495d9405200bdc4e9b35c52ebe4500dcfafd0733a969f01bc293027b00991

Analysis

Strong private key

Good. The private key associated with this certificate is secure.

Strong signature algorithm

Good. This certificate uses a strong signature algorithm.

Certificate matches hostname

Good. The provided certificate matches the expected hostnames.

Certificate dates match

Good. The certificate is valid for use at this point of time.

Certificate has not been revoked

Good. This certificate has not been revoked.

Certificate satisfies Apple's CT compliance requirements

Good. This certificate satisfies Apple's CT requirements at present.

Certificate Trust

Determining whether a certificate is considered valid is a complicated process that depends on the exact configuration of the validating party. For trust to be established, the certificate must form a chain that ends with a trusted root. In this section we evaluate the server's certificate against major root stores.

Platform	Trusted
Apple
Google AOSP
Microsoft
Mozilla

Certificate Chain

For a server certificate to be valid, it must be presented as part of a complete and valid certificate chain. The last certificate in the chain should be the root and is usually not included in the configuration.

Leaf certificate

skiff.com | ee4bc3a
Not After: 12 Jun 2025 10:46:16 UTC (expires in 1 month 5 days)
Authentication: RSA 2048 bits (SHA256withRSA)
View details

Names	.api.skiff.com .app.skiff.com *.skiff.com skiff.com
Subject DN	CN=skiff.com
Subject Key Identifier	279bb6a34800bc5cbe73960792c2f47fff243015
Serial	6405c2b7fec0ba79e74462fa732a1845e30
Not Before	14 Mar 2025 10:46:17 UTC
Not After	12 Jun 2025 10:46:16 UTC
Validity period	90 days
Key Usage	digitalSignature, keyEncipherment
Extended Key Usage	serverAuth, clientAuth
Must Staple	No
Issuer
Issuer DN	CN=R11, O=Let's Encrypt, C=US
Certification Authority	Let's Encrypt
Validation Type	Domain Validation (DV)
Authority Key Identifier	keyid:c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Parent Certificate	http://r11.i.lencr.org/
CRL	http://r11.c.lencr.org/49.crl
OCSP	http://r11.o.lencr.org
Certificate Transparency
Signed Certificate Timestamps	14 Mar 2025 11:44:48 UTC \| Cloudflare 'Nimbus2025' \| Qualified 14 Mar 2025 11:44:48 UTC \| Google 'Xenon2025h1' log \| Qualified
Fingerprints
SHA1	e13a64e5cdd05e085c0d20e61a2473a694751898
SHA256	ee4bc3a18b27b873b4c9a1e67a257b52a7cf68d8cebb3b7256bf855010dbbdbc
SPKI SHA256	4ed495d9405200bdc4e9b35c52ebe4500dcfafd0733a969f01bc293027b00991

Intermediate certificate

R11 | 591e9ce
Not After: 12 Mar 2027 23:59:59 UTC (expires in 1 year 10 months)
Authentication: RSA 2048 bits (SHA256withRSA)
View details

Subject DN	CN=R11, O=Let's Encrypt, C=US
Subject Key Identifier	c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
Serial	8a7d3e13d62f30ef2386bd29076b34f8
Not Before	13 Mar 2024 00:00:00 UTC
Not After	12 Mar 2027 23:59:59 UTC
Validity period	1095 days
Key Usage	digitalSignature, keyCertSign, cRLSign
Extended Key Usage	clientAuth, serverAuth
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Not Applicable
Authority Key Identifier	keyid:79b459e67bb6e5e40173800888c81a58f6e99b6e
Parent Certificate	http://x1.i.lencr.org/
CRL	http://x1.c.lencr.org/
CA certificate	Yes (pathlen 0)
Fingerprints
SHA1	696db3af0dffc17e65c6a20d925c5a7bd24dec7e
SHA256	591e9ce6c863d3a079e9fabe1478c7339a26b21269dde795211361024ae31a44
SPKI SHA256	6ddac18698f7f1f7e1c69b9bce420d974ac6f94ca8b2c761701623f99c767dc7

Root certificate

ISRG Root X1 | 96bcec0
Not After: 04 Jun 2035 11:04:38 UTC (expires in 10 years 28 days)
Authentication: RSA 4096 bits (SHA256withRSA)
View details

Subject DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Subject Key Identifier	79b459e67bb6e5e40173800888c81a58f6e99b6e
Serial	8210cfb0d240e3594463e0bb63828b00
Not Before	04 Jun 2015 11:04:38 UTC
Not After	04 Jun 2035 11:04:38 UTC
Key Usage	keyCertSign, cRLSign
Issuer
Issuer DN	CN=ISRG Root X1, O=Internet Security Research Group, C=US
Certification Authority	Let's Encrypt
Validation Type	Self-signed
CA certificate	Yes (pathlen unlimited)
Fingerprints
SHA1	cabd2a79a1076a31f21d253635cb039d4329a5e8
SHA256	96bcec06264976f37460779acf28c5a7cfe8a3c0aae11a8ffcee05c0bddf08c6
SPKI SHA256	0b9fa5a59eed715c26c1020c711b4f6ec42d58b0015e14337a39dad301c5afc3

Analysis

Certificate chain is correct

Good. This chain contains all the right certificates and in the right order.

DANE (443)

DNS-based Authentication of Named Entities (DANE) is a bridge between DNSSEC and TLS. In one possible scenario, DANE can be used for public key pinning, building on an existing publicly-trusted certificate. In another approach, it can be used to completely bypass the CA ecosystem and establish trust using DNSSEC alone.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Cookies

Cookies are small chunks of text that are sent between your browser and a website. They are often essential to the operation of the site and sometimes contain sensitive information. Session cookies sent from secure sites must be explicitly marked as secure to prevent being obtained by active network attackers.

Test passed

Everything seems to be well configured. Well done.

HTTP Cookie: __cf_bm

Cookie value. As far as the cookie RFC is concerned, the value is an opaque string which only the application should interpret.Value	xggFXu2Sh2_HFpx9lFcHogiQ2uodsuc.7sderYww0wc-1746563775-1.0.1.1-MZjl1U9t3JDV2EOoIBQsql0TzBY4.plhBP7WPAhy9qv95ersN4n1znsN9ztVuBJGzPqfI9HgZSclXFG8B4DEbhf065VPN.iHyq.yM8WwrEg
Cookie domain. When domain is implied (not explicitly set in a cookie), most browsers (but not IE) treat the cookie as host-only, meaning that no other server can overwrite it.Domain	skiff.com
Cookie path. This field can't be used as security measure, but it could be of use to avoid cookie name collision in non-adversarial contexts.Path	/
Cookies are designed to always expire. Session cookies are truly ephemeral and remain cached until the browser is closed. The Expires and Max-Age cookie attributes can be used to specify that a cookie should stay alive for longer.Expires	Tue May 06 21:06:15 UTC 2025 (27 minutes)
The HttpOnly flag prevents the cookie from being accessed from JavaScript, thus making them more difficult to obtain after a successful XSS attack.HttpOnly
The Secure flag signals to browsers that the cookie should be transmitted only over an encrypted channel.Secure
Normally, when a browser makes a request to a web site, it sends all associated cookies. This is not always desirable, because it might allow third-party sites to perform site actions under the identity of the user. This attack is known as Cross-Site Request Forgery. With SameSite cookies (still in development, but already supported in some browsers), you can choose to be more strict. The possible values are 'lax' and 'strict'.SameSite

Analysis

Cookie is secure

Good. This cookie is marked secure, which means that it won't ever be transmitted over plaintext. As such, it's not vulnerable to the Sidejacking attack.

Analysis

All cookies are secure

Great. All observed cookies are marked secure.

HTML Content

On virtually all web sites, HTML markup, images, style sheets, JavaScript, and other page resources arrive not only over multiple connections but possibly from multiple servers and sites spread across the entire Internet. For a page to be properly encrypted, it’s necessary that all the content is retrieved over HTTPS. In practice, that’s very often not the case, leading to mixed content security problems.

Test passed

Everything seems to be well configured. Well done.

Encryption of Embedded Resources

In this section we look at the transport security of all embedded resources. Mixed active content occurs when there are unprotected scripts or styles embedded in a page. This is typically not allowed by modern browsers. Mixed passive content (images, videos and such) are typically allowed, but shouldn't be present.

14 script(s)
14 out of 14 are secure View all

Status	Link
Encrypted	https://skiff.com/...-c67a75d1b6f99dc8.js
Encrypted	https://skiff.com/....d2d435d860b99f32.js
Encrypted	https://skiff.com/...-062862dc05b2a255.js
Encrypted	https://skiff.com/...-d47be7805f476874.js
Encrypted	https://skiff.com/...-d1b1cba67afa2ea3.js
Encrypted	https://skiff.com/...-622175efd111644e.js
Encrypted	https://skiff.com/...-d40a32cad8c3896a.js
Encrypted	https://skiff.com/...-733b4ff0acde79d3.js
Encrypted	https://skiff.com/...-d8ad5edc6ed1ebeb.js
Encrypted	https://skiff.com/...-c29ae4e23de6a84a.js
Encrypted	https://skiff.com/...-cde1a75ee259b914.js
Encrypted	https://skiff.com/...-48bf91cf5b3371be.js
Encrypted	https://skiff.com/...eQ/_buildManifest.js
Encrypted	https://skiff.com/...toeQ/_ssgManifest.js

2 CSS file(s)
2 out of 2 are secure View all

Status	Link
Encrypted	https://skiff.com/styles/global.css
Encrypted	https://skiff.com/...b71082df31b64d38.css

1 media file(s)
1 out of 1 are secure View all

Status	Link
Encrypted	https://cdn.sanity.io/...0bc585f8f-163x64.svg

Encryption of Outbound Links

Ideally, an encrypted page should only have links that lead to other encrypted pages. If plaintext links are used, passive network attackers can see where people go after they visit your web site. It's also possible that some sensitive information is leaked in the Referer header.

3 link(s)
3 out of 3 are encrypted View all

Status	Link
Encrypted	https://github.com/skiff-org
Encrypted	https://app.skiff.com/...34-922e-bdad09d0e4be
Encrypted	https://app.skiff.com/...98-95b2-6a85085fdbde

HTTP Strict Transport Security

HTTP Strict Transport Security (HSTS) vastly improves security of the network encryption layer. With HSTS enabled, browsers no longer allow clicking through certificate warnings errors, which are typically trivial to exploit. Additionally, they will no longer submit insecure (plaintext) requests to the site in question, even if asked.

Test passed

Everything seems to be well configured. Well done.

HSTS Policy Main host

URL from which this policy was obtained.Location	https://www.skiff.com/
Specifies policy duration. Once activated, HSTS stays in force until this time lapses. Browsers update policy cache duration every time they receive a new HSTS header from a site.max‑age	31,536,000 seconds (about 1 year)
When present, this directive forces HSTS activation on allsubdomains. For best security, HSTS should be deployed on the bare domain name (e.g., example.com) and all its subdomains.includeSubDomains
Presence of this directive indicates that a web site wishes to permanently use HSTS and that its policy information should be preloaded (embedded in browsers).preload

Analysis

Policy is valid

OK. Your HSTS policy uses correct syntax.

Long policy age

Your HSTS policy has a long max-age value, which offers better protection.

Policy covers subdomains

When subdomains are included, network attackers are unable to manufacture arbitrary subdomains to manipulate cookies and trick users.

Redirection from HTTP to HTTPS is to a parent host that activates HSTS

For simplicity, it's best when there is a redirection on port 80 that sends clients to the same host on port 443. In that case, you know that HSTS will always be activated on the host. There isn't a same-host redirection in this instance, but the redirection is to a parent that activates HSTS via the includeSubDomains directive. That's all right.

Starting point: http://www.skiff.com

Current redirection: https://skiff.com/

Policy preloaded

Excellent. This host is covered by a preloaded HSTS policy.

Preloaded host: skiff.com; includeSubDomains=true

Apex policy activated on every page visit

The homepage of this web site contains a link to a resource on the apex hostname. This approach will ensure that, whenever HSTS is activated on the main site, it's activated on the apex hostname too.

Resource URL: https://skiff.com/_next/static/chunks/polyfills-c67a75d1b6f99dc8.js

HSTS Policy Apex host

URL from which this policy was obtained.Location	https://skiff.com/
Specifies policy duration. Once activated, HSTS stays in force until this time lapses. Browsers update policy cache duration every time they receive a new HSTS header from a site.max‑age	31,536,000 seconds (about 1 year)
When present, this directive forces HSTS activation on allsubdomains. For best security, HSTS should be deployed on the bare domain name (e.g., example.com) and all its subdomains.includeSubDomains
Presence of this directive indicates that a web site wishes to permanently use HSTS and that its policy information should be preloaded (embedded in browsers).preload

Analysis

Policy is valid

OK. Your HSTS policy uses correct syntax.

Long policy age

Your HSTS policy has a long max-age value, which offers better protection.

Policy covers subdomains

When subdomains are included, network attackers are unable to manufacture arbitrary subdomains to manipulate cookies and trick users.

Preload intent declared

Good. With the preload directive set, browsers have a green light to embed the HSTS policy.

Redirection from HTTP to HTTPS to the same host

Good. The redirection from HTTP to HTTPS is to the same host. This approach ensures that HSTS is activated on the hostname when it's accessed via plaintext.

Policy preloaded

Excellent. This host is covered by a preloaded HSTS policy.

Preloaded host: skiff.com; includeSubDomains=true

HTTP Public Key Pinning

HTTP Public Key Pinning (HPKP) enables site operators to restrict which certificates are considered valid for their domain names. With a valid HPKP configuration, sites can defeat man in the middle (MITM) attacks using fraudulent or misissued certificates. HPKP is an advanced feature, suitable for use by only high-profile web sites.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Content Security Policy

Content Security Policy (CSP) is a security mechanism that allows web sites control how browsers process their pages. In essence, sites can restrict what types of resources are loaded and from where. CSP policies can be used to defend against cross-site scripting, prevent mixed content issues, as well as report violations for investigation.

Test passed

Everything seems to be well configured. Well done.

content-security-policy

default-src	'self'
script-src	'self' https://static.cloudflareinsights.com
style-src	'self' This parameter shouldn't be used because it reenables insecure behavior that CSP disables by default.'unsafe-inline'
object-src	'none'
base-uri	'self'
connect-src	'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com
font-src	'self' data:
frame-src	'self' https://platform.twitter.com/ https://www.youtube.com
img-src	'self' https://cdn.sanity.io https://i.ytimg.com
report-uri	https://cspreports.skiff.com
worker-src	'self'

Analysis

Inline styles are allowed

This policy allows inline styles. Although they are not as bad as inline scripts in terms of security, an injection bug in script area would allow the attacker to modify page appearance.

Mixed content not blocked

This CSP policy doesn't use any of the directives designed to handle mixed content. Consider using the 'block-all-mixed-content' and 'upgrade-insecure-requests' directives as appropriate to ensure that no mixed content is allowed.

Form targets not restricted

The 'form-action' directive is not explicitly set. Because this directive doesn't fall back to default sources, this means that all targets are allowed.

content-security-policy-report-only

report-uri

https://cspreports.skiff.com

Analysis

Mixed content not blocked

This CSP policy doesn't use any of the directives designed to handle mixed content. Consider using the 'block-all-mixed-content' and 'upgrade-insecure-requests' directives as appropriate to ensure that no mixed content is allowed.

Form targets not restricted

The 'form-action' directive is not explicitly set. Because this directive doesn't fall back to default sources, this means that all targets are allowed.

Analysis

CSP policy detected

Header: content-security-policy

Value: default-src 'self'; script-src 'self' https://static.cloudflareinsights.com; script-src-elem 'self' 'unsafe-inline' https://platform.twitter.com/js/ https://platform.twitter.com/widgets.js https://www.youtube.com https://cdn.matomo.cloud/skiff.matomo.cloud/matomo.js https://skiff.matomo.cloud/plugins/HeatmapSessionRecording/; style-src 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://hooks.slack.com/services/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 https://sdd9dua4.apicdn.sanity.io/ https://skiff.matomo.cloud https://skiff.zendesk.com https://static.cloudflareinsights.com https://marketing-site.skiff.com; font-src 'self' data:; frame-src 'self' https://platform.twitter.com/ https://www.youtube.com; img-src 'self' https://cdn.sanity.io https://i.ytimg.com; manifest-src 'self'; media-src 'self'; report-uri https://cspreports.skiff.com; worker-src 'self'

Location: https://skiff.com/

CSP report-only policy detected

Header: content-security-policy-report-only

Value: require-trusted-types-for 'script'; report-uri https://cspreports.skiff.com

Location: https://skiff.com/

Subresource Integrity

Subresource Integrity (SRI) is a new standard that enables browsers to verify the integrity of embedded page resources (e.g., scripts and stylesheets) when they are loaded from third-party web sites. With SRI deployed, remote resources can be used safely, without fear of them being modified by malicious parties.

Test passed

Everything seems to be well configured. Well done.

14 script(s)
14 out of 14 are secure View all

Status	Link
Local	/_next/static/QXBU6fqLxrgrpdWiGtoeQ/_buildManifest.js
Local	/_next/static/QXBU6fqLxrgrpdWiGtoeQ/_ssgManifest.js
Local	/_next/static/chunks/1691-d8ad5edc6ed1ebeb.js
Local	/_next/static/chunks/2075-733b4ff0acde79d3.js
Local	/_next/static/chunks/2158-c29ae4e23de6a84a.js
Local	/_next/static/chunks/4847.d2d435d860b99f32.js
Local	/_next/static/chunks/6828-622175efd111644e.js
Local	/_next/static/chunks/7329-cde1a75ee259b914.js
Local	/_next/static/chunks/8571-d47be7805f476874.js
Local	/_next/static/chunks/main-d1b1cba67afa2ea3.js
Local	/_next/static/chunks/pages/_app-d40a32cad8c3896a.js
Local	/_next/static/chunks/pages/index-48bf91cf5b3371be.js
Local	/_next/static/chunks/polyfills-c67a75d1b6f99dc8.js
Local	/_next/static/chunks/webpack-062862dc05b2a255.js

2 CSS file(s)
2 out of 2 are secure View all

Status	Link
Local	/_next/static/css/b71082df31b64d38.css
Local	/styles/global.css

Analysis

No remote resources

The homepage of this site doesn't contain any remote resources so SRI is not needed.

Expect CT

Expect-CT is a deprecated response HTTP header designed to enable web sites to monitor problems related to their Certificate Transparency (CT) compliance. Should any CT issues arise, browsers that supported this header will submit reports to the specified reporting endpoint. Chrome was the browser that introduced support for this response header, but later deprecated it and removed it in version 107.

Feature not applicable, not implemented, or disabled

Your server doesn't support this feature.

Analysis

Deploy Expect-CT to enable reporting

An Expect-CT policy enables web sites to monitor for any problems related to their Expect-CT compliance, detecting potentially serious issues quickly. When issues arise, compliant browsers will submit reports to the specified reporting endpoints. Before CT became required for all public certificates the Expect-CT was also used to require CT, but that use case no longer applies.

Frame Options

The X-Frame-Options header controls page framing, which occurs when a page is incorporated into some other page, possibly on a different site. If framing is allowed, attackers can employ clever tricks to make victims perform arbitrary actions on your site; they do this by showing their web site while forwarding the victim's clicks to yours.

Test passed

Everything seems to be well configured. Well done.

Analysis

Header information

Name: x-frame-options

Value: DENY

Framing blocked

Good. Your site doesn't allow page framing from any other page.

XSS Protection

Some browsers ship with so-called XSS Auditors, built-in defenses against XSS. Although these defenses work against simple reflective XSS attacks, they can be abused by skillful attackers to add weaknesses to otherwise secure web sites. These dangers are present in both filtering and blocking modes. At this time, the Safari browser ships with its XSS defenses enabled by default. For this reason, the best approach is to explicitly disable this functionality.

Test passed

Everything seems to be well configured. Well done.

Analysis

Header information

Name: x-xss-protection

Value: 0

Browser XSS protection disabled

Great. XSS protection is explicitly disabled, making this web site safe even with browsers that have this functionality enabled by default.

Content Type Options

Some browsers use a technique called content sniffing to override response MIME types provided by HTTP servers and interpret responses as something else (usually HTML). This behavior, which could potentially lead to security issues, should be disabled by attaching an X-Content-Type-Options header to all responses.

Test passed

Everything seems to be well configured. Well done.

Analysis

Header information

Name: x-content-type-options

Value: nosniff

Valid configuration

Good. Your configuration is valid. This means that browsers won't try to guess file MIME type on this web site.

Public Report | skiff.com

skiff.com

Domain Name System

Email

WWW

DNS Zone

Nameserver Names

Nameserver Addresses

Start of Authority (SOA) Record

Analysis

Backing DNS Queries

DNS Records

DNS Records

Backing DNS Queries

DNSSEC

Analysis

Useful DNSSEC Tools

Certification Authority Authorization

CAA Policy Information

Analysis

Email (SMTP)

Analysis

Email TLS (SMTP)

Email Certificates (SMTP)

Email DANE (SMTP)

SPF

SPF Policy Information Main policy

Analysis

DMARC

DMARC Policy Information

Analysis

MTA Strict Transport Security

MTA-STS Policy Indicator

Analysis

MTA-STS Policy

Analysis

Certificate: mta-sts.skiff.com

Analysis

Certificate Chain

Analysis

SMTP TLS Reporting

TLS-RPT Policy

Analysis

HTTP (80)

URL: http://skiff.com/

Analysis

URL: http://www.skiff.com/

Analysis

HTTP (443)

URL: https://skiff.com/

URL: https://www.skiff.com/

WWW TLS

TLS Configuration: skiff.com (2606:4700:3108:0:0:0:ac42:285e)

Analysis

TLS Configuration: www.skiff.com (2606:4700:3108:0:0:0:ac42:2ba2)

Analysis

TLS Configuration: www.skiff.com (2606:4700:3108:0:0:0:ac42:285e)

Analysis

TLS Configuration: skiff.com (2606:4700:3108:0:0:0:ac42:2ba2)

Analysis

TLS Configuration: www.skiff.com (172.66.40.94)

Analysis

TLS Configuration: skiff.com (172.66.40.94)

Analysis

TLS Configuration: www.skiff.com (172.66.43.162)

Analysis

TLS Configuration: skiff.com (172.66.43.162)

Analysis

WWW Certificates

Certificate: skiff.com

Analysis

Certificate Trust

Certificate Chain

Analysis

Certificate: www.skiff.com

Analysis

Certificate Trust

Certificate Chain

Analysis

Certificate: skiff.com