3 ms·
I didn't think so, but I mentioned it because the Wikipedia article on Merkle-Damgård hashes (http://en.wikipedia.org/wiki/Merkle–Damgård_construction http://en
by wzdd 13y ago
I didn't think so, but I mentioned it because the Wikipedia article on Merkle-Damgård hashes (http://en.wikipedia.org/wiki/Merkle–Damgård_construction http://en.wikipedia.org/wiki/Merkle–Damgård_construction) talks about length extension attacks only in the context of hash collisions: "Length extension — once an attacker has one collision, he can find more very cheaply."
- tptacek 13y agoThat's actually a relatively new finding, and a very cool attack (I assume we're talking about Joux multicollisions).
- pbsd 13y agoMulti-collisions is another thing. What Wikipedia means is that once you find m and m' s.t. H(m) = H(m'), then you've also found the collision H(m || X) = H(m' || X) for whatever X, i.e., unlimited collisions.