>> Recently there has been some discussion on the Internet regarding so >> called null-prefix attacks, see >> http://www.thoughtcrime.org/papers/null-prefix-attacks.pdf. Is openssl >> vulnerable to this attack?. > > The attack is not an attack against SSL/TLS, but against > implementation of HTTPS (RFC 2818) , FTPS(RFC 4217) , ... > > Callers of the openssl library which were wrong > can/were fixed without any change in openssl > >From what I understand, this does not impact any applications other than webbrowsers, since IIRC they are the only ones that having a 'host header' which is part of the request and can be used to detect a proper website by the browser. I believe other services using SSL/TLS do not have those. So an incorrect CN wouldn''t really make any difference. Also, since part of the authenticity check where the null-prefix issue is relevant is only performed clientside. Also this should only impact servercertificates, since clientcertificates would be handled by the server, and with these the requested host is irrelevant since the ssl happens at a different layer.
Probably there are some discrepancies in what I said, so please add any comments you can come up with! HTH Regards, Serge Fonville ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List [email protected] Automated List Manager [email protected]
