SSL Report: uat.zapto.org (47.90.121.218)
Assessed on:  Fri, 12 Sep 2025 10:07:06 UTC | Clear cache

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Summary
Overall Rating
T
If trust issues are ignored: A
0
20
40
60
80
100
Certificate
 
Protocol Support
 
Key Exchange
 
Cipher Strength
 

Visit our documentation page for more information, configuration guides, and books. Known issues are documented here.
This server's certificate is not trusted, see below for details.
This server's certificate chain is incomplete. Grade capped to B.
This site works only in browsers with SNI support.
This server supports TLS 1.3.  MORE INFO »
HTTP Strict Transport Security (HSTS) with long duration deployed on this server.  MORE INFO »
Certificate #1: RSA 2048 bits (SHA256withRSA)
Server Key and Certificate #1
Subject data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=
Common names data-uat.hb.gov.hk
Alternative names data-uat.hb.gov.hk   MISMATCH
Serial Number 7c99e5714fe4dd3c90d6ad51197d8ffd6ef4333d
Valid from Fri, 11 Apr 2025 06:32:41 UTC
Valid until Sat, 11 Apr 2026 06:32:41 UTC (expires in 6 months and 29 days)
Key RSA 2048 bits (e 65537)
Weak key (Debian) No
Issuer Hongkong Post e-Cert SSL CA 3 - 17
AIA: http://www1.eCert.gov.hk/root/ecert_ssl_ca_3-17.crt
Signature algorithm SHA256withRSA
Extended Validation No
Certificate Transparency Yes (certificate)
OCSP Must Staple No
Revocation information CRL, OCSP
CRL: http://crl1.eCert.gov.hk/crl/eCertSCA3-17CRL1.crl
OCSP: http://ocsp1.eCert.gov.hk
Revocation status Good (not revoked)
DNS CAA No (more info)
Trusted No   NOT TRUSTED (Why?)
Mozilla  Apple  Android  Java  Windows 


Additional Certificates (if supplied)
Certificates provided 1 (1637 bytes)
Chain issues Incomplete


Certification Paths
Path #1: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 In trust store Hongkong Post Root CA 3   Self-signed
Fingerprint SHA256: 5a2fc03f0c83b090bbfa40604b0988446c7636183df9846e17101a447fb8efd6
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
Path #2: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 Extra download Hongkong Post Root CA 3
Fingerprint SHA256: 00482341b104a0de6e0f1d508db84cb514f7494fe04982133a5c750136c55dc8
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
4 In trust store GlobalSign   Self-signed
Fingerprint SHA256: cbb522d7b7f127ad6a0113865bdf1cd4102e7d0759af635a7cf4720dc963c53b
Pin SHA256: cGuxAXyFXFkWm61cF4HPWX8S0srS9j0aSqN0k4AP+4A=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 In trust store Hongkong Post Root CA 3   Self-signed
Fingerprint SHA256: 5a2fc03f0c83b090bbfa40604b0988446c7636183df9846e17101a447fb8efd6
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
Path #2: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 Extra download Hongkong Post Root CA 3
Fingerprint SHA256: 00482341b104a0de6e0f1d508db84cb514f7494fe04982133a5c750136c55dc8
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
4 In trust store GlobalSign   Self-signed
Fingerprint SHA256: cbb522d7b7f127ad6a0113865bdf1cd4102e7d0759af635a7cf4720dc963c53b
Pin SHA256: cGuxAXyFXFkWm61cF4HPWX8S0srS9j0aSqN0k4AP+4A=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 In trust store Hongkong Post Root CA 3   Self-signed
Fingerprint SHA256: 5a2fc03f0c83b090bbfa40604b0988446c7636183df9846e17101a447fb8efd6
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
Path #2: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 Extra download Hongkong Post Root CA 3
Fingerprint SHA256: 00482341b104a0de6e0f1d508db84cb514f7494fe04982133a5c750136c55dc8
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
4 In trust store GlobalSign   Self-signed
Fingerprint SHA256: cbb522d7b7f127ad6a0113865bdf1cd4102e7d0759af635a7cf4720dc963c53b
Pin SHA256: cGuxAXyFXFkWm61cF4HPWX8S0srS9j0aSqN0k4AP+4A=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 Extra download Hongkong Post Root CA 3
Fingerprint SHA256: 00482341b104a0de6e0f1d508db84cb514f7494fe04982133a5c750136c55dc8
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
4 In trust store GlobalSign   Self-signed
Fingerprint SHA256: cbb522d7b7f127ad6a0113865bdf1cd4102e7d0759af635a7cf4720dc963c53b
Pin SHA256: cGuxAXyFXFkWm61cF4HPWX8S0srS9j0aSqN0k4AP+4A=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 In trust store Hongkong Post Root CA 3   Self-signed
Fingerprint SHA256: 5a2fc03f0c83b090bbfa40604b0988446c7636183df9846e17101a447fb8efd6
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
Path #2: Not trusted (invalid certificate [Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a])
1 Sent by server data-uat.hb.gov.hk
Fingerprint SHA256: 76e7fe8565109429384d0d5a412b7c9d2820309c0e8dd567f63af2e38752408a
Pin SHA256: DmRLMgf0/nKSBBf6chwfwQHD2AstZizLn/TxbA8sNmA=

RSA 2048 bits (e 65537) / SHA256withRSA
2 Extra download Hongkong Post e-Cert SSL CA 3 - 17
Fingerprint SHA256: cb730c3a5fe958b8bdc5b363892c9f530b33f98a43ce3c2578fce096b4ae233c
Pin SHA256: SUe0dPoWC5QKoJyXReRB3haevgxOd9ZVd5sn7N65/DY=

RSA 2048 bits (e 65537) / SHA256withRSA
3 Extra download Hongkong Post Root CA 3
Fingerprint SHA256: 00482341b104a0de6e0f1d508db84cb514f7494fe04982133a5c750136c55dc8
Pin SHA256: JUHlO6WzsHrL5wl6xKA+BAwRz3ptSmfLIT1Vi1AWegY=

RSA 4096 bits (e 65537) / SHA256withRSA
4 In trust store GlobalSign   Self-signed
Fingerprint SHA256: cbb522d7b7f127ad6a0113865bdf1cd4102e7d0759af635a7cf4720dc963c53b
Pin SHA256: cGuxAXyFXFkWm61cF4HPWX8S0srS9j0aSqN0k4AP+4A=

RSA 2048 bits (e 65537) / SHA256withRSA

Click here to expand

Configuration
Protocols
TLS 1.3 Yes
TLS 1.2 No
TLS 1.1 No
TLS 1.0 No
SSL 3 No
SSL 2 No


Cipher Suites
# TLS 1.3 (server has no preference)
TLS_AES_128_GCM_SHA256 (0x1301)   ECDH x25519 (eq. 3072 bits RSA)   FS 128
TLS_AES_256_GCM_SHA384 (0x1302)   ECDH x25519 (eq. 3072 bits RSA)   FS 256
TLS_CHACHA20_POLY1305_SHA256 (0x1303)   ECDH x25519 (eq. 3072 bits RSA)   FS 256


Handshake Simulation
Android 8.1 -   TLS 1.3 TLS_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
Android 9.0 -   TLS 1.3 TLS_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
Chrome 69 / Win 7  R RSA 2048 (SHA256)   TLS 1.2 > h2   TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
Chrome 70 / Win 10 -   TLS 1.3 TLS_AES_128_GCM_SHA256   ECDH x25519  FS
Chrome 80 / Win 10  R -   TLS 1.3 TLS_AES_128_GCM_SHA256   ECDH x25519  FS
Firefox 62 / Win 7  R RSA 2048 (SHA256)   TLS 1.2 > h2   TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
Firefox 73 / Win 10  R -   TLS 1.3 TLS_AES_128_GCM_SHA256   ECDH x25519  FS
Java 11.0.3 -   TLS 1.3 TLS_AES_128_GCM_SHA256   ECDH secp256r1  FS
Java 12.0.1 -   TLS 1.3 TLS_AES_128_GCM_SHA256   ECDH secp256r1  FS
OpenSSL 1.1.0k  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
OpenSSL 1.1.1c  R -   TLS 1.3 TLS_AES_256_GCM_SHA384   ECDH x25519  FS
Safari 12.1.2 / MacOS 10.14.6 Beta  R -   TLS 1.3 TLS_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
Safari 12.1.1 / iOS 12.3.1  R -   TLS 1.3 TLS_CHACHA20_POLY1305_SHA256   ECDH x25519  FS
# Not simulated clients (Protocol mismatch)
Android 2.3.7   No SNI 2 Protocol mismatch (not simulated)
Android 4.0.4 Protocol mismatch (not simulated)
Android 4.1.1 Protocol mismatch (not simulated)
Android 4.2.2 Protocol mismatch (not simulated)
Android 4.3 Protocol mismatch (not simulated)
Android 4.4.2 Protocol mismatch (not simulated)
Android 5.0.0 Protocol mismatch (not simulated)
Android 6.0 Protocol mismatch (not simulated)
Android 7.0 Protocol mismatch (not simulated)
Android 8.0 Protocol mismatch (not simulated)
Baidu Jan 2015 Protocol mismatch (not simulated)
BingPreview Jan 2015 Protocol mismatch (not simulated)
Chrome 49 / XP SP3 Protocol mismatch (not simulated)
Firefox 31.3.0 ESR / Win 7 Protocol mismatch (not simulated)
Firefox 47 / Win 7  R Protocol mismatch (not simulated)
Firefox 49 / XP SP3 Protocol mismatch (not simulated)
Googlebot Feb 2018 Protocol mismatch (not simulated)
IE 6 / XP   No FS 1   No SNI 2 Protocol mismatch (not simulated)
IE 7 / Vista Protocol mismatch (not simulated)
IE 8 / XP   No FS 1   No SNI 2 Protocol mismatch (not simulated)
IE 8-10 / Win 7  R Protocol mismatch (not simulated)
IE 11 / Win 7  R Protocol mismatch (not simulated)
IE 11 / Win 8.1  R Protocol mismatch (not simulated)
IE 10 / Win Phone 8.0 Protocol mismatch (not simulated)
IE 11 / Win Phone 8.1  R Protocol mismatch (not simulated)
IE 11 / Win Phone 8.1 Update  R Protocol mismatch (not simulated)
IE 11 / Win 10  R Protocol mismatch (not simulated)
Edge 15 / Win 10  R Protocol mismatch (not simulated)
Edge 16 / Win 10  R Protocol mismatch (not simulated)
Edge 18 / Win 10  R Protocol mismatch (not simulated)
Edge 13 / Win Phone 10  R Protocol mismatch (not simulated)
Java 6u45   No SNI 2 Protocol mismatch (not simulated)
Java 7u25 Protocol mismatch (not simulated)
Java 8u161 Protocol mismatch (not simulated)
OpenSSL 0.9.8y Protocol mismatch (not simulated)
OpenSSL 1.0.1l  R Protocol mismatch (not simulated)
OpenSSL 1.0.2s  R Protocol mismatch (not simulated)
Safari 5.1.9 / OS X 10.6.8 Protocol mismatch (not simulated)
Safari 6 / iOS 6.0.1 Protocol mismatch (not simulated)
Safari 6.0.4 / OS X 10.8.4  R Protocol mismatch (not simulated)
Safari 7 / iOS 7.1  R Protocol mismatch (not simulated)
Safari 7 / OS X 10.9  R Protocol mismatch (not simulated)
Safari 8 / iOS 8.4  R Protocol mismatch (not simulated)
Safari 8 / OS X 10.10  R Protocol mismatch (not simulated)
Safari 9 / iOS 9  R Protocol mismatch (not simulated)
Safari 9 / OS X 10.11  R Protocol mismatch (not simulated)
Safari 10 / iOS 10  R Protocol mismatch (not simulated)
Safari 10 / OS X 10.12  R Protocol mismatch (not simulated)
Apple ATS 9 / iOS 9  R Protocol mismatch (not simulated)
Yahoo Slurp Jan 2015 Protocol mismatch (not simulated)
YandexBot Jan 2015 Protocol mismatch (not simulated)

Click here to expand

(1) Clients that do not support Forward Secrecy (FS) are excluded when determining support for it.
(2) No support for virtual SSL hosting (SNI). Connects to the default site if the server uses SNI.
(3) Only first connection attempt simulated. Browsers sometimes retry with a lower protocol version.
(R) Denotes a reference browser or client, with which we expect better effective security.
(All) We use defaults, but some platforms do not use their best protocols and features (e.g., Java 6 & 7, older IE).
(All) Certificate trust is not checked in handshake simulation, we only perform TLS handshake.


Protocol Details
ROBOT (vulnerability) No (more info)
Forward Secrecy Yes (with most browsers)   ROBUST (more info)
ALPN Yes   h2
Session resumption (tickets) No
OCSP stapling No
Strict Transport Security (HSTS) Yes
max-age=31536000;includeSubDomains
HSTS Preloading Not in: Chrome  Edge  Firefox  IE 
Public Key Pinning (HPKP) No (more info)
Public Key Pinning Report-Only No
Public Key Pinning (Static) No (more info)
Supported Named Groups x25519, secp256r1, secp384r1, secp521r1, ffdhe2048, ffdhe3072 (server preferred order)
SSL 2 handshake compatibility No
0-RTT enabled No


HTTP Requests
1 https://uat.zapto.org/  (HTTP/1.1 404 )
1
Referrer-Policy no-referrer
Strict-Transport-Security max-age=31536000;includeSubDomains
Content-Security-Policy object-src 'none';script-src 'self' 'unsafe-inline' 'unsafe-eval'; frame-ancestors 'self';frame-src 'self';img-src 'self';font-src 'self';connect-src 'self';base-uri 'self';form-action 'self';
Permissions-Policy fullscreen=self; camera=none; microphone=none; geolocation=none; payment=none; notifications=none; accelerometer=none; gyroscope=none; magnetometer=none; speaker-selection=none; usb=none; xr-spatial-tracking=none;battery=none;interest-cohort=none;
X-Download-Options noopen
X-Permitted-Cross-Domain-Policies none
X-Frame-Options DENY
X-Content-Type-Options nosniff
X-XSS-Protection 1; mode=block
Content-Type text/html
Content-Length 207
Date Fri, 12 Sep 2025 10:06:40 GMT
Connection close
Server


Miscellaneous
Test date Fri, 12 Sep 2025 10:06:30 UTC
Test duration 35.705 seconds
HTTP status code 404
HTTP server signature -
Server hostname -


Why is my certificate not trusted?

There are many reasons why a certificate may not be trusted. The exact problem is indicated on the report card in bright red. The problems fall into three categories:

  1. Invalid certificate
  2. Invalid configuration
  3. Unknown Certificate Authority

1. Invalid certificate

A certificate is invalid if:

2. Invalid configuration

In some cases, the certificate chain does not contain all the necessary certificates to connect the web server certificate to one of the root certificates in our trust store. Less commonly, one of the certificates in the chain (other than the web server certificate) will have expired, and that invalidates the entire chain.

3. Unknown Certificate Authority

In order for trust to be established, we must have the root certificate of the signing Certificate Authority in our trust store. SSL Labs does not maintain its own trust store; instead we use the store maintained by Mozilla.

If we mark a web site as not trusted, that means that the average web user's browser will not trust it either. For certain special groups of users, such web sites can still be secure. For example, if you can securely verify that a self-signed web site is operated by a person you trust, then you can trust that self-signed web site too. Or, if you work for an organisation that manages its own trust, and you have their own root certificate already embedded in your browser. Such special cases do not work for the general public, however, and this is what we indicate on our report card.

4. Interoperability issues

In some rare cases trust cannot be established because of interoperability issues between our code and the code or configuration running on the server. We manually review such cases, but if you encounter such an issue please feel free to contact us. Such problems are very difficult to troubleshoot and you may be able to provide us with information that might help us determine the root cause.

SSL Report v2.4.1