2 ms·
This could, in theory, allow discovering IDs of sessions that are either active or cached on the server end. IDs are passed in clear between SSL peers, so being
by eps 13y ago
This could, in theory, allow discovering IDs of sessions that are either active or cached on the server end. IDs are passed in clear between SSL peers, so being able to recover them doesn't compromise the security of the protocol.
That said, this can be used to estimate the size of the server's session list and to covertly measure and monitor the volume of its activity. This can come handy in some cases, but then splicing into server's Internet connection and passively listening to the traffic would yield the same information with much less fuss.
- tptacek 13y agoC memcmp() timing channels are extremely difficult in practice to exploit, even at relatively close proximity to targets, so I'm not sure how practical any of this is.
- pipeep 13y agoIt's probably not practical, but it doesn't hurt to fix or remove (it's not used internally in OpenSSL) the code anyways. I submitted a pull request to Ruby, where the code was copied to, and is used: https://github.com/ruby/ruby/pull/591 https://github.com/ruby/ruby/pull/591 .