A vulnerability has been reported in OpenSSL, which can be exploited by malicious people to bypass certain security restrictions.
The vulnerability is caused due to an error within the "SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG" workaround in the SSL/TLS server code. This can be exploited by e.g. sniffing the session identifier and downgrading the cached ciphersuite prior to the legitimate client resuming the session, potentially leading to the client using a weaker ciphersuite.
Successful exploitation requires that the server uses the internal caching mechanisms of OpenSSL and the "SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG" flag (e.g. enabled via the "SSL_OP_ALL" option).
Note: In versions prior to 0.9.8j, this can further be exploited to force the use of a ciphersuite disabled on the server side.
The vulnerability is reported in all versions prior to 0.9.8q or 1.0.0c.
Solution: Update to version 0.9.8q or 1.0.0c or apply patches.
Do you have additional information related to this advisory?
Please provide information about patches, mitigating factors, new versions, exploits, faulty patches, links, and other relevant data by posting comments to this Advisory. You can also send this
information to firstname.lastname@example.org