SSH? [LWN.net]

SSH?

Posted Jun 21, 2011 1:48 UTC (Tue) by djao (guest, #4263)
In reply to: SSH? by dlang
Parent article: WebOS: the other Linux-based mobile platform

You keep mentioning the type of attacks where "someone's laptop/desktop was compromised and their SSH keys were then used to go login to other systems." This is not a fair comparison. The reason SSH keys are attacked in this way is because SSH keys are actually used. Believe it or not, SSL also supports client-side keys for authentication. The reason why you never hear about this feature getting attacked in SSL is because, I believe, the number of people in the world who use this feature in SSL is approximately zero. If they were actually used, then the same attack would also work against SSL.

My whole point all along is that SSL's failure to achieve marketplace acceptance is the one thing that above all else renders SSL useless as a security protocol. It hardly seems fair to attack SSH on this basis. A security protocol or protocol feature, such as SSL client-side keys, which nobody uses is certainly invulnerable to attack, but it also does not contribute to security in the slightest.

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SSH?

Posted Jun 21, 2011 3:26 UTC (Tue) by dlang (guest, #313) [Link]

you are misunderstanding me.

I am not attacking ssh because of the cases where the client certs have been compromised, I am mentioning them and saying that such attacks do not count as SSH vulnerabilities (they count as bad deployment decisions on how to use SSH, relying solely on the possession of the client side cert, not requiring anything else)

another poster claimed that SSL without CA validation is meaningless, someone else pointed out that that basically matched what SSH does, and that SSH is therefor vulnerable to the same types of attacks as SSL without CA validation. So the question I am raising is, given that there is far more extensive use of SSH, can anyone show attacks against this supposed severe mitm vulnerability?

programming bugs in SSH don't count (which is what most CVE things are)

attacks that involve compromising the client key don't count as they aren't mitm attacks.