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Error code: ssl_error_no_cypher_overlap when trying with localhost

  • 6 replies
  • 95 have this problem
  • 2 views
  • Last reply by NoahSUMO

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I am trying to connect to localhost. I am getting

Secure Connection Failed An error occurred during a connection to localhost. Cannot communicate securely with peer: no common encryption algorithm(s). (Error code: ssl_error_no_cypher_overlap)

What setting should i do to enable the localhost in new version?

I am trying to connect to localhost. I am getting Secure Connection Failed An error occurred during a connection to localhost. Cannot communicate securely with peer: no common encryption algorithm(s). (Error code: ssl_error_no_cypher_overlap) What setting should i do to enable the localhost in new version?

All Replies (6)

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Does it have any effect if you disable libPKIX?

You can test that by disabling libPKIX support in Firefox, but it is not recommended to leave it disabled on the long run for security and vulnerability reasons.

  • about:config page: security.use_mozillapkix_verification = false

Did this work in previous Firefox versions? If that is the case then in what version did this work?

Every now and then some cipher suits that are weak and vulnerable are removed, so it is possible that your server software needs an update to support stronger cipher suits.

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In the previous versions, when i used to change security.ssl3.rsa_rc4_128_md5 property to true, localhost would work. However i dont remember in which version did it work. In 29.0 version, i do not see the above said configuration. Same localhost works when i start tomcat server and hit an HTTP url but doesnt work for the HTTPS url.

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Any Luck? I am still struggling. about:config page: security.use_mozillapkix_verification = false also did not have any effect. I guess Firefox version 15 or 16 worked with md5 change.

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The security.ssl3.rsa_rc4_128_md5 is still present on the about:config page, so it is still supported. You can try to disable (toggle to false) all security.ssl3.* prefs and enable one at the time to see if it works with one of the other cipher suits.

If you can get it to work that way then enable more of the cipher suits until it stop. You need to clear the "Active Logins" via "History > Clear Recent History" after every change from true to false (false to true is probably OK).

Modified by cor-el

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Disabling/toggling all security.ssl3.* (that were true) blocks ALL SSL connections, including this page/site, Google, and my own server where I just disabled SSLv3 due to a security issue.

Meanwhile, as much as this pains me to point out, Chrome has no problem connecting to any of the above...

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This is not the proper thread to discuss the new SSL 3.0 exploit. This thread is from August. And the answer provided by cor-el was not prepared specifically for this exploit just revealed by Google on October 14th.

Please ask a new question to have this properly answered. Locking this old thread to avoid further confusion.


For anyone worried about the SSL 3.0 exploit, please install this addon: https://addons.mozilla.org/en-US/firefox/addon/ssl-version-control/

Or change the about:config preference security.tls.version.min from 0 (sslv3) to 1 (tls 1.0).

And read: https://blog.mozilla.org/security/2014/10/14/the-poodle-attack-and-the-end-of-ssl-3-0/

Modified by NoahSUMO