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SSL_ERROR_NO_CYPHER_OVERLAP only in private mode

  • 8 replies
  • 3 have this problem
  • 12 views
  • Last reply by cor-el

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I encountered this weird case, when a certain web page works in regular mode, but not in private browsing.

The error in private mode is:

Secure Connection Failed

An error occurred during a connection to a.private.server.com:8443. Cannot communicate securely with peer: no common encryption algorithm(s). Error code: SSL_ERROR_NO_CYPHER_OVERLAP

   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.
I encountered this weird case, when a certain web page works in regular mode, but not in private browsing. The error in private mode is: Secure Connection Failed An error occurred during a connection to a.private.server.com:8443. Cannot communicate securely with peer: no common encryption algorithm(s). Error code: SSL_ERROR_NO_CYPHER_OVERLAP 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.

All Replies (8)

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I suspect it might be due to missing client certificate*. Firefox in Private mode does not ask for it (i have several certificates installed).

"star" - in which case the error is very misleading (which is apparently an unwritten rule in X.509 land...)

Modified by xerces9

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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

What do the security warning codes mean



SSL_ERROR_NO_CYPHER_OVERLAP Your server apparently doesn't offer any cipher suites necessary to establish a secure https connection that are supported in Firefox. You can check what kind of cipher suites Firefox can make use of by visiting; https://www.ssllabs.com/ssltest/viewMyClient.html

Firefox will just show the SSL_ERROR_NO_CYPHER_OVERLAP error when encountered any site using the RC4 cipher.

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Hi xerces9,

Your system details show that your participating in Firefox Studies and I see this extension installed :

"ETP Search Volume Study 1.2"

It might have something to do with it .... (just a thought, though)

Also see :

https://github.com/mozilla/etp-search-volume-study

And this bug report :

https://bugzilla.mozilla.org/show_bug.cgi?id=1532678

You could disable the extension (for now) as a test .....

(edit : typo ... )

Modified by McCoy

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FredMcD said

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


Why would this only be a problem in private mode and not in normal mode?

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That I don't know.

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I did some testing and it seems to be a bug. see https://bugzilla.mozilla.org/show_bug.cgi?id=1554152

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Good work. Hopefully, they can sort it out.

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See also:

  • Bug 1362079 - Display a more helpful error when a SSL handshake fails due to a client certificate