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For PCI compliance I was required to protect our server against BEAST attacks. While I have correctly configured the apache / openssl settings to pass a scan, these settings have effectively limited the client browsers that can securely transact on the sites https side.

We are using Cenots 6.5 Final, OpenSSL 1.0.1e-fips 11 Feb 2013

I cannot find any information on how to update or add either specific or all ciphers to OpenSSL.

Are cipher suites distributed within the OpenSSL program OR are ciphers suites add-ons?, if they are add-ons how do you update them?

  • Thanks for the replies, I guess I wasn't clear in my question. I have been using these sites (SSL LABS) and I am trying to add the ciphers that they are recommending. I cannot find any information anywhere on how to do so. Example: ssllabs.com/ssltest/… If you look at the "Cipher suites in order of preference" the first cipher is ECDHE_RSA_WITH_AES_256_CBC_SHA384 (ECDHE-RSA-AES256-CBC-SHA384) my current openssl does not support this, so I'd like to add this and others. – sr_1436048 Sep 5 '14 at 9:21
  • If your current OpenSSL version does not support the cipher suite that you want to use, you must update OpenSSL to a version that does support it. – RoraΖ Sep 5 '14 at 11:38
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Basically agreeeing but adding several points:

Cipher suites are in the OpenSSL code (technically the library not the executable). Proper OpenSSL already implements nearly all the standard suites so there's nothing useful to add. However RedHat and AIUI also CentOS packages until about the end of 2013 excluded from the build all Elliptic Curve (ECC) features: this knocked out ECDSA certificates (not widely used, at least yet); ECDH (static) and AECDH (anon) key-exchanges which practically no one used; and ECDHE (ephemeral) key-exchange which is more and more used and is highly desirable -- it provides Forward Secrecy like DHE but more efficiently, and for one important browser (IE) more consistently available. So updating to a more recent OpenSSL package may help. Or getting upstream https://www.openssl.org/source and building it yourself, but that's quite a bit more work.

@Rook The sslshopper page is fairly old and no longer accurate. To disable SSLv2 (good) it uses a method which also disables TLSv1.1 and 1.2 (very bad; 1.1 especially is a much more targeted defense to BEAST than RC4). It correctly excludes ADH but fails to exclude AECDH (preferably via aNULL). And with no explanation or background, it discourages users from discovering these mistakes. I recommend instead https://community.qualys.com/blogs/securitylabs/2013/08/05/configuring-apache-nginx-and-openssl-for-forward-secrecy et al and/or https://wiki.mozilla.org/Security/Server_Side_TLS .

If your server is public (and PCI compliance is an issue mostly for servers that are public) https://www.ssllabs.com/ssltest/ (Qualys) provides a wider and more up-to-date test including some explanations.

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A fully updated system will still have insecure or weak cipher-suites enabled. You can run a tool such as TestSSLServer, written by Tomas Pornin which will give you a list of cipher suites that are vulnerable to BEAST and CRIME.

After you have identified the specific set of insecure cipher suites that affect your system, you can disable them in Apache's SSL configuration.

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