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Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

I can't connect to all sites, the error code is "SEC_ERROR_UNKNOWN_ISSUER", can you help me?

  • 11 uphendule
  • 1 inale nkinga
  • 411 views
  • Igcine ukuphendulwa ngu NotReality_

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I currently use FF version 63.0.3 on Windows 10, I have tried removing cert8.db, running FF in safe mode, even reinstalling FF, but it still didn't work. I also only use SMADAV and Windows Defender as antivirus. Only the official Mozilla site can be accessed.

As i recall, this problem started when I accidentally switched to a site. Could you help me?

And sorry if my grammar is bad, English is not my first language.

Okulungisiwe ngu NotReality_

Isisombululo esikhethiwe

Okay, thank you, i already solve the problem.

I run a small scan using a newly downloaded Malwarebytes, and then it find many Adware and other Malware too. Now, i able to connect to Google and any major site freel just like before.

Thank you for all your help.

Funda le mpendulo ngokuhambisana nalesi sihloko 👍 0

All Replies (11)

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There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connection certificates and send their own.

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

Websites don't load - troubleshoot and fix error messages

http://kb.mozillazine.org/Error_loading_websites


  • MOZILLA_PKIX_ERROR_MITM_DETECTED
  • uses an invalid security certificate SSL_ERROR_BAD_CERT_DOMAIN
  • configured their website improperly

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

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I don't think this fix my issue, as a said before, i don't have any of this software nor any software that have capability to intercept secure connection.

Any help please?

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What are your protection programs?

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

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Hi NotReality_, we need a little more information to diagnose this.

When you are viewing the error page, and click the "Advanced" button, then click

SEC_ERROR_UNKNOWN_ISSUER

to expand another panel showing a coded version of the certificate Firefox refuses to accept. You can copy that certificate and paste it into a reply for a volunteer to decode and review.

Or try it yourself on a site like the following and look at the "Issuer" section:

https://certlogik.com/decoder/

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You can check if there is more detail available about the issuer of the certificate.

  • click the "Advanced" button show more detail
  • click the blue error text (SEC_ERROR_UNKNOWN_ISSUER) to show the certificate chain
  • click "Copy text to clipboard" and paste the base64 certificate chain text in a reply

If clicking the blue error text doesn't provide the certificate chain then try these steps to inspect the certificate.

  • open the Servers tab in the Certificate Manager
    • Options/Preferences -> Privacy & Security
      Certificates: View Certificates -> Servers: "Add Exception"
  • paste the URL of the website (https://xxx.xxx) in it's Location field

Let Firefox retrieve the certificate -> "Get Certificate"

  • click the "View" button and inspect the certificate

You can see detail like the issuer of the certificate and intermediate certificates in the Details tab.

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jscher2000 said

Hi NotReality_, we need a little more information to diagnose this. When you are viewing the error page, and click the "Advanced" button, then click SEC_ERROR_UNKNOWN_ISSUER to expand another panel showing a coded version of the certificate Firefox refuses to accept. You can copy that certificate and paste it into a reply for a volunteer to decode and review. Or try it yourself on a site like the following and look at the "Issuer" section: https://certlogik.com/decoder/

Sorry for a very, very late respond. I need to goes offline for few days.

As you ask, here the certificate.


BEGIN CERTIFICATE----- MIIDmjCCAoKgAwIBAgIUNycgHW53+Rx0cCuE5zYLOsSphu0wDQYJKoZIhvcNAQEL BQAwVDElMCMGA1UEAxMcR29vZ2xlIEludGVybmV0IEF1dGhvcml0eSBHMzEeMBwG A1UEChMVR29vZ2xlIFRydXN0IFNlcnZpY2VzMQswCQYDVQQGEwJVUzAeFw0xODEx MDcwODU5MDBaFw0xOTAxMzAwODU5MDBaMGgxFzAVBgNVBAMMDnd3dy5nb29nbGUu Y29tMRMwEQYDVQQKDApHb29nbGUgTExDMRYwFAYDVQQHDA1Nb3VudGFpbiBWaWV3 MRMwEQYDVQQIDApDYWxpZm9ybmlhMQswCQYDVQQGEwJVUzCCASIwDQYJKoZIhvcN AQEBBQADggEPADCCAQoCggEBAJZbZ5MLkHm1ma716ARZhRmdSUeHz/UE4XNkiCMD ltUpPh0nVn0jYbgLgYyqEjtMcLeTRGDICm9T7wjmk2nC0VcRB6SBGqkX7CavNnar SkY1jEtmQ3J0frmVoNXcfO9SVwlXB+/vGBCUmKRa3Ax3M7cxam9HKvHu9BU78zfi voFC1eqhZ4Ll7KitMtSkr/o+aCZBM6z0ppvJSiPHlEegGZDol/eIKf3Wf7NOHanT jKj/UlVc4AQfgnbVyU6D6T+9W+JLc/YNUUJ1u8ArjQ05fnDs2phwwZdZyWL/9Lrv iiDLgN5Z+cX+xlC2O7/kahsWmFoWmUJG9gemI1lLjeORdTcCAwEAAaNQME4wDAYD VR0TAQH/BAIwADAOBgNVHQ8BAf8EBAMCAbgwGQYDVR0RBBIwEIIOd3d3Lmdvb2ds ZS5jb20wEwYDVR0lBAwwCgYIKwYBBQUHAwEwDQYJKoZIhvcNAQELBQADggEBAHzv nklOOqctDwYoh5qMBlfIbbleqJVpxzQFWRjXyLKi0tx0D480jghW4cw24Ac8krGu YUwbOXZ9x9ASZJhtXD7HoiRIkYeGqCQr8lMLw7DjFQ35VtSBlBJW6m2HNW9/9e4q 1ljXRU4vxzbAszSIgIyDc6QFfDt0k0KQhXe8akLuXnpwvJkMVmG8GtzvOk3dO98i v7TUEwHiXKKK00nvyyBc8ZgzFuhgOVB6WVHqqm6L6kBKZ16Ee2EoyuDbYakF9XZu 8BGM0ObM2eRR4hV4mVmCBmGr7F2bauF4c/eGzBv7j6KV7+rXD5aEQKaJeAS9OM7u DB3LrxLpr05WRk8NQ+Q= -----END CERTIFICATE-----
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Certificate Checks Status Check Information Valid To 30 Jan 2019 ( 57 days ) Weak-Key Does not use a key on our blacklist - this is good Key-Size 2048 bits Signature Algorithm Strong (sha256WithRSAEncryption)


Certificate Summary Subject RDN Value Common Name (CN) www.google.com Organization (O) Google LLC Locality (L) Mountain View State (ST) California Country (C) US

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Okay, as i recall there was a site that make me suddenly redirected. After that, i find a strange activity in my Task Manager, you know some kind of background app. Maybe that is the problem?

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The certificate issuer information looks normal, and I think Firefox should accept that.

Do you want to try deleting the cert9.db file and having Firefox regenerate it? The steps for that are mentioned in this article: What do the security warning codes mean?

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NotReality_ said

Okay, as i recall there was a site that make me suddenly redirected. After that, i find a strange activity in my Task Manager, you know some kind of background app. Maybe that is the problem?

If you think your system might have become infected, please see: Troubleshoot Firefox issues caused by malware.

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Isisombululo Esikhethiwe

Okay, thank you, i already solve the problem.

I run a small scan using a newly downloaded Malwarebytes, and then it find many Adware and other Malware too. Now, i able to connect to Google and any major site freel just like before.

Thank you for all your help.