Showing questions tagged:

Firefox 143 (Fedora distribution) throws SEC_ERROR_UNKNOWN_ISSUER error on many websites

When trying to access many popular websites with Firefox on my Fedora 43 installation, I am greeted with a security warning page with the SEC_ERROR_UNKNOWN_ISSUER error. … (read more)

When trying to access many popular websites with Firefox on my Fedora 43 installation, I am greeted with a security warning page with the SEC_ERROR_UNKNOWN_ISSUER error. For most of these websites I can simply accept and continue, but HSTS-only sites will not permit this.

Affected websites include but are not limited to (based on exceptions in the certificates section of Firefox settings):

Any help in resolving this is appreciated.

Solved Archived 5 174

Did Not Connect: Potential Security Issue

Did Not Connect: Potential Security Issue Firefox detected a potential security threat and did not continue to nrega.nic.in because this website requires a secure connect… (read more)

Did Not Connect: Potential Security Issue

Firefox detected a potential security threat and did not continue to nrega.nic.in because this website requires a secure connection.

What can you do about it?

nrega.nic.in has a security policy called HTTP Strict Transport Security (HSTS), which means that Firefox can only connect to it securely. You can’t add an exception to visit this site.

Probably nothing, since it’s likely there’s a problem with the site itself.

Solved Archived 1 388

Error code: PR_END_OF_FILE_ERROR

Clear Error code: PR_END_OF_FILE_ERROR This is only on Amazon.com. Secure Connection Failed An error occurred during a connection to www.amazon.com. PR_END_OF_FILE_E… (read more)

Clear Error code: PR_END_OF_FILE_ERROR This is only on Amazon.com. Secure Connection Failed

An error occurred during a connection to www.amazon.com. PR_END_OF_FILE_ERROR

Error code: PR_END_OF_FILE_ERROR

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this problem.

Learn more…

Solved Archived 1 359

Google Ads login error

Hi Love Firefox and use it every day to manage clients Google Ads accounts. Updated to latest version and now I'm getting this warning when I'm trying to access ads.googl… (read more)

Hi Love Firefox and use it every day to manage clients Google Ads accounts. Updated to latest version and now I'm getting this warning when I'm trying to access ads.google.com Doesn't appear that I can add an exception, is there a work around that I can use. Look forward to hearing back. Thanks in advance

Paul

Solved 2 41

Firefox does not accept letzencrypt from https://www.thegamer.com

Site: https://www.thegamer.com Firefox refuses to load the site, it does not even show the certificate when clicking on the lock. Using the certificate manager, add excep… (read more)

Site: https://www.thegamer.com Firefox refuses to load the site, it does not even show the certificate when clicking on the lock. Using the certificate manager, add exception does not work too, it just refuses to store the certificate. But at least THERE I can VIEW the certificate, which proves it is valid and FIREFOX is at fault:

https://www.ssllabs.com/ssltest/analyze.html?d=www.thegamer.com&latest shows "IO exception" when trying to check the CRL, but gives an A+. Yet Firefox does not even give me the "Continue anyway" possibility. This it tiering, I hate using google chrome based browsers, but of course, it works there. Server 2025, only MS-defender at its default settings.

Subject Name Common Name thegamer.com Issuer Name Country US Organization Let's Encrypt Common Name E8 Validity Not Before Mon, 13 Oct 2025 23:03:42 GMT Not After Sun, 11 Jan 2026 23:03:41 GMT Subject Alt Names DNS Name

DNS Name thegamer.com Public Key Info Algorithm Elliptic Curve Key Size 256 Public Value 04:0E:95:16:C4:A2:23:9D:81:AD:D7:70:4C:4B:A5:F7:68:0E:33:E2:A0:1C:81:6D:0F:1C:F5:C8:EF:5B:C8:64:AD:15:86:5D:5E:E6:FA:A6:DB:41:86:A5:F0:28:7A:45:F4:8D:75:B3:18:43:E9:0F:7C:75:10:AE:F8:A0:04:7B:D5 Miscellaneous Serial Number 06:6C:A7:00:7C:ED:C0:50:E2:FD:4F:6C:A0:8C:0F:86:2B:AD Signature Algorithm ECDSA with SHA-384 Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 D0:D5:E8:73:9E:6D:B1:2D:EC:5D:47:0D:70:BF:58:1C:AC:A5:D3:89:20:6D:54:15:09:E8:42:9C:82:F7:4F:8F SHA-1 53:E6:54:B5:37:0F:4B:23:BE:73:8A:6B:37:6B:BE:A6:A5:86:E4:5B [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority No [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Digital Signature Extended Key Usages Purposes Server Authentication, Client Authentication Subject Key ID Key ID 53:6A:02:33:30:1C:AD:4D:3B:F2:9F:4D:6D:E4:33:26:31:69:8F:61 Authority Key ID Key ID 8F:0D:13:A2:F6:2E:7E:D1:50:6C:33:18:38:5D:59:8E:23:72:91:CA CRL Endpoints Distribution Point http://e8.c.lencr.org/46.crl Authority Info (AIA) Location http://e8.i.lencr.org/ Method CA Issuers Certificate Policies Policy Certificate Type ( 2.23.140.1.2.1 ) Value Domain Validation Embedded SCTs Log ID 0E:57:94:BC:F3:AE:A9:3E:33:1B:2C:99:07:B3:F7:90:DF:9B:C2:3D:71:32:25:DD:21:A9:25:AC:61:C5:4E:21 Signature Algorithm SHA-256 ECDSA Version 1 Timestamp Tue, 14 Oct 2025 00:02:12 GMT Log ID 19:86:D4:C7:28:AA:6F:FE:BA:03:6F:78:2A:4D:01:91:AA:CE:2D:72:31:0F:AE:CE:5D:70:41:2D:25:4C:C7:D4 Signature Algorithm SHA-256 ECDSA Version 1 Timestamp Tue, 14 Oct 2025 00:02:12 GMT


Subject Name Country US Organization Let's Encrypt Common Name E8 Issuer Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Validity Not Before Wed, 13 Mar 2024 00:00:00 GMT Not After Fri, 12 Mar 2027 23:59:59 GMT Public Key Info Algorithm Elliptic Curve Key Size 384 Public Value 04:D1:65:F2:5E:DC:4B:B4:0C:02:9C:D2:B2:FA:EE:E9:6C:AB:3A:AE:38:A1:F4:D4:39:32:33:C5:42:D4:CC:33:0C:34:C7:21:20:90:70:5C:E8:62:2F:1C:71:B3:42:D7:79:BE:46:0D:C1:DB:47:A1:13:A0:C7:DF:81:26:63:3B:D4:8D:1D:F6:3D:82:33:32:F6:F4:2B:E7:F5:96:3A:B4:13:67:18:7B:6B:3E:8D:48:D9:EA:DE:ED:AE:6D:3E:87:4C Miscellaneous Serial Number 63:95:93:63:C2:4E:70:82:71:59:18:BF:C3:D7:ED:56 Signature Algorithm SHA-256 with RSA Encryption Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 83:62:4F:D3:38:C8:D9:B0:23:C1:8A:67:CB:7A:9C:05:19:DA:43:D1:17:75:B4:C6:CB:DA:D4:5C:3D:99:7C:52 SHA-1 54:31:7E:B0:76:5F:0B:C6:74:85:51:84:EB:83:74:B4:19:9E:46:55 [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority Yes [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Digital Signature, Certificate Signing, CRL Signing Extended Key Usages Purposes Client Authentication, Server Authentication Subject Key ID Key ID 8F:0D:13:A2:F6:2E:7E:D1:50:6C:33:18:38:5D:59:8E:23:72:91:CA Authority Key ID Key ID 79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E CRL Endpoints Distribution Point http://x1.c.lencr.org/ Authority Info (AIA) Location http://x1.i.lencr.org/ Method CA Issuers Certificate Policies Policy Certificate Type ( 2.23.140.1.2.1 ) Value Domain Validation


Subject Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Issuer Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Validity Not Before Thu, 04 Jun 2015 11:04:38 GMT Not After Mon, 04 Jun 2035 11:04:38 GMT Public Key Info Algorithm RSA Key Size 4096 Exponent 65537 Modulus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iscellaneous Serial Number 00:82:10:CF:B0:D2:40:E3:59:44:63:E0:BB:63:82:8B:00 Signature Algorithm SHA-256 with RSA Encryption Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 96:BC:EC:06:26:49:76:F3:74:60:77:9A:CF:28:C5:A7:CF:E8:A3:C0:AA:E1:1A:8F:FC:EE:05:C0:BD:DF:08:C6 SHA-1 CA:BD:2A:79:A1:07:6A:31:F2:1D:25:36:35:CB:03:9D:43:29:A5:E8 [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority Yes [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Certificate Signing, CRL Signing Subject Key ID Key ID 79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E

Solved 1 192

bank site

I have never ever had a problem getting into my bank account until this evening. Says it is insecure. How can this happen? I really need to get into my account! … (read more)

I have never ever had a problem getting into my bank account until this evening.

Says it is insecure.

How can this happen? I really need to get into my account!

Solved 1 140

Intermittent “SEC_ERROR_OCSP_INVALID_SIGNING_CERT” error on my site in Firefox

Hello, I run a movie and drama-related website: https://tvmon.com.co/. Recently, I’ve noticed that Firefox occasionally throws the following error when trying to access t… (read more)

Hello, I run a movie and drama-related website: https://tvmon.com.co/. Recently, I’ve noticed that Firefox occasionally throws the following error when trying to access the site:

"Secure Connection Failed An error occurred during a connection to tvmon.com.co. . The OCSP response contains an invalid signing certificate. Error code: SEC_ERROR_OCSP_INVALID_SIGNING_CERT"

This issue is very strange because:

  1. The site loads fine in Chrome, Edge, and Safari.
  1. My SSL/TLS certificate is valid, up-to-date, and passes external tests (SSL Labs, etc.).
  1. The error only appears occasionally in Firefox, refreshing sometimes fixes it, sometimes not.
  1. Hosting and server logs show no issues at all.

I suspect this is related to Firefox’s stricter OCSP validation, but I’m not sure how to debug or resolve it. Since my site streams drama and movie content, this error is frustrating for users who rely on Firefox.

Has anyone else experienced this intermittent OCSP signing certificate error? Is there a known fix or workaround for Firefox-specific validation issues?

Solved 1 215

Mozzila rejects connection with a spesific site.

Untill last night i could conect with that site https://imtw.ru and its sub forums without eny problem . Today when i press the link i recieve a message that the connecti… (read more)

Untill last night i could conect with that site https://imtw.ru and its sub forums without eny problem . Today when i press the link i recieve a message that the connection is rejected "Failure to secure connection". As you van see it has the https:// infront and i repeat i was able to connect last night. What may be wrong?

Solved 6 178

Neiman Marcus Gift Certificate

Please help me purchase a NM Gift Certificate for my daughter Caroline Campbell. She has an account with you but I do not and I'm overwhelmed by the process. Lisa Nichol … (read more)

Please help me purchase a NM Gift Certificate for my daughter Caroline Campbell. She has an account with you but I do not and I'm overwhelmed by the process. Lisa Nichol [edited email from community support forum]

Locked Archived 2 116

i can't do a search. I keep getting "problem loading page" and "secured connection failed"

i can't do a search. I keep getting "problem loading page" and "secured connection failed" This is happening on both my windows 7 computer and my windows 10 computer. The… (read more)

i can't do a search. I keep getting "problem loading page" and "secured connection failed" This is happening on both my windows 7 computer and my windows 10 computer. The same thing is happening if I try a google search as well.

Solved 1 106

Firefox is not allowing me to open any website including https://support.mozilla.org/1/firefox/141.0.3/WINNT/en-US/firefox-help

I am able to open all these sites in Edge and Chrome. Firefox is not allowing me to open any website including https://support.mozilla.org/1/firefox/141.0.3/WINNT/en-US/f… (read more)

I am able to open all these sites in Edge and Chrome. Firefox is not allowing me to open any website including https://support.mozilla.org/1/firefox/141.0.3/WINNT/en-US/firefox-help

Here is one for www.theepochtimes.com Firefox blocked your visit to this site because the signature on the certificate provided for linkprotect.cudasvc.com isn’t valid.

Error code: SEC_ERROR_BAD_SIGNATURE

View Certificate

https://linkprotect.cudasvc.com/url?a=https%3a%2f%2flists.theepochtimes.com%2flinks%2fdYekYfa9b%2fHhryKHE6n%2fm46Mv1lM35xm%2ffPxqlcxbEy&c=E,1,ZCIg6L-Y-rIKvrOC91Rng41YHEp3yXHnFOrkZ-dEbsu8eJmVYw5eygLlFsHlgdf1Tmry7UZgvuCl6QoNJHES1kUyjNFgc3z8J5-hU70LqRt8blmn&typo=1

Peer’s certificate has an invalid signature.

HTTP Strict Transport Security: false HTTP Public Key Pinning: false

Certificate chain:


BEGIN CERTIFICATE-----

MIIB3TCCAYKgAwIBAgIIOvW4RpHf51AwCgYIKoZIzj0EAwIwTTELMAkGA1UEBhMC TFQxFTATBgNVBAoMDE5vcmRWUE4gUy5BLjEnMCUGA1UEAwweTm9yZFZQTiBTLkEu IC1UaHJlYXRQcm90ZWN0aW9uMB4XDTI1MDgyNTE5MTA1NFoXDTI2MDgyNTE5MTU1 NFowJDEiMCAGA1UEAwwZKi5saW5rcHJvdGVjdC5jdWRhc3ZjLmNvbTBZMBMGByqG SM49AgEGCCqGSM49AwEHA0IABGrx92NDDePfCVmGrn4StYMr6XU2mdhqpiE51CmT XEnX6cYCaE1KyVrw09JFubcGZSmUUllYqKjKop6A4uds/5SjdTBzMB0GA1UdDgQW BBTUcdvR66YYJKl/X5qqiMfeJn5XtjATBgNVHSUEDDAKBggrBgEFBQcDATA9BgNV HREENjA0ghkqLmxpbmtwcm90ZWN0LmN1ZGFzdmMuY29tghdsaW5rcHJvdGVjdC5j dWRhc3ZjLmNvbTAKBggqhkjOPQQDAgNJADBGAiEA2a31LBw2Ab2UixVdpVQpJwx0 hW5mLG/KCvuyrACqUQ8CIQDAnirOaJT0OuV3d4jeznV7DaLdY7RqVDXyuGNZwXDZ Fw==


END CERTIFICATE-----
Solved Archived 2 198

How to remove "security exception" for a certificate-expired site

When I bring up the certificate-expired URL <https://oaklandwiki.org/> in Firefox 149.0 on Windows 11 I am told "You have added a security exception for this site.… (read more)

When I bring up the certificate-expired URL

<https://oaklandwiki.org/>

in Firefox 149.0 on Windows 11 I am told "You have added a security exception for this site." But not how to remove it. How do I do that? I did not see anything in Settings or about:config; did I miss it?

Solved 4 66

Connecting problems

Secure Connection Failed An error occurred during a connection to nrega.nic.in. Peer’s Certificate has been revoked. Error code: SEC_ERROR_REVOKED_CERTIFICATE The page… (read more)

Secure Connection Failed

An error occurred during a connection to nrega.nic.in. Peer’s Certificate has been revoked.

Error code: SEC_ERROR_REVOKED_CERTIFICATE

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this problem.
Solved Archived 1 85

PR_CONNECT_RESET_ERROR when trying to web browse.

I'm getting a PR_CONNECT_RESET_ERROR on my PC when trying to web browse. Same problem with other browsers. Was working fine till a few days ago The URL box has 'Not Secur… (read more)

I'm getting a PR_CONNECT_RESET_ERROR on my PC when trying to web browse. Same problem with other browsers. Was working fine till a few days ago The URL box has 'Not Secure' before each URL address I try. Have looked up solutions on YT to no avail eg clearing cache etc

My Laptop has no problem with this.

Solved Archived 4 368

Certificate Error only on Firefox only on one computer

Firefox is giving me an error on https://stemgateway.nasa.gov but the site is perfectly accessible using MS Edge and using Firefox on another computer. I uninstalled and … (read more)

Firefox is giving me an error on https://stemgateway.nasa.gov but the site is perfectly accessible using MS Edge and using Firefox on another computer. I uninstalled and reinstalled Firefox, changed the proxy settings to not use a proxy, tested a VPN, and changed DNS servers. Below is a picture of the error and of the certificate which seems to be present in Firefox already.

Solved Archived 9 237