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firefox 58, Error code: SEC_ERROR_UNKNOWN_ISSUER

  • 4 replies
  • 19 have this problem
  • 1 view
  • Last reply by noname126

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While browsing everything was fine, then firefox updated itself to ver 58, so i closed and reopened it to let it finish. Now ALL websites are showing "Your connection is not secure" Error code: SEC_ERROR_UNKNOWN_ISSUER.

I tried the following, in no particular order: - reinstalling firefox - deleting profile folder - changing settings to: no proxy - checking my pc with malwarebytes - disabling Kaspersky - tried out ver 59 beta

Nothing works. I am forced to use opera for the time being, no issues there.

As for certificate chain. When clicking on Advanced -> error code, this is all i can copy to clipboard: "" https://www.youtube.com/

Peer’s Certificate issuer is not recognized.

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

Certificate chain: ""

I have never encountered this problem before, thoughts?

While browsing everything was fine, then firefox updated itself to ver 58, so i closed and reopened it to let it finish. Now ALL websites are showing "Your connection is not secure" Error code: SEC_ERROR_UNKNOWN_ISSUER. I tried the following, in no particular order: - reinstalling firefox - deleting profile folder - changing settings to: no proxy - checking my pc with malwarebytes - disabling Kaspersky - tried out ver 59 beta Nothing works. I am forced to use opera for the time being, no issues there. As for certificate chain. When clicking on Advanced -> error code, this is all i can copy to clipboard: "" https://www.youtube.com/ Peer’s Certificate issuer is not recognized. HTTP Strict Transport Security: true HTTP Public Key Pinning: true Certificate chain: "" I have never encountered this problem before, thoughts?

Chosen solution

Hello, im suprised i didnt get any more replies. Oh well. Thanks for fixing that bug.

If anyone else still has this error in firefox version 58.0.1 - Remove kaspersky certificate, - immediately reinstall it from

 (C:\ProgramData\Kaspersky Lab\AVP18.0.0\Data\Cert\ (fake)Kaspersky Anti-Virus Personal Root Certificate.cer) 

- and tick all the trust boxes.

That should fix it once and for all.

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All Replies (4)

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nevermind, I left firefox open for a few minutes and it fixed itself. I have no idea how. I guess it needed to shadow update something.

Modified by noname126

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If you encounter this again there is this related article https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

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OK, I have encountered this problem again today. Thank you for the link James. Turning off the encrypted connection scanning indeed stops the error. It also disabled kaspersky add-on.

However, i found strong evidence suggesting the 'problem is 100% with Firefox certificates settings'.

For some reason, as a default kaspersky certificate doesnt have any trust. When i tick all 3 trust boxes, and confirm, the error disappears and EVERYTHING works. No need to turn off connection scanning. The real issue is, upon closing Firefox, all the trust i had set up disappears. Every, single, time.

The certificate is genuine, doesnt have any duplicates and I reinstalled it from C:\ProgramData\Kaspersky Lab\AVP18.0.0\Data\Cert\ (fake)Kaspersky Anti-Virus Personal Root Certificate.cer as per instructions on malwaretips forum: https://malwaretips.com/threads/firefox-kaspersky-error-sec_error_unknown_issuer.67919/

Can someone please confirm if its a bug, or am i doing something wrong?

Here is how i set up certificate trust: options -> privacy and security -> Certificates -> view certificates -> Authorities -> AO Kaspersky Lab -> Kasperky antivirus personal root certificate -> Edit trust -> tick all 3 boxes -> ok ->ok -> close options

Modified by noname126

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Chosen Solution

Hello, im suprised i didnt get any more replies. Oh well. Thanks for fixing that bug.

If anyone else still has this error in firefox version 58.0.1 - Remove kaspersky certificate, - immediately reinstall it from

 (C:\ProgramData\Kaspersky Lab\AVP18.0.0\Data\Cert\ (fake)Kaspersky Anti-Virus Personal Root Certificate.cer) 

- and tick all the trust boxes.

That should fix it once and for all.

Modified by noname126