2 ms·
because you can create two hashes that match, but you cannot create a hash that matches an arbitrary hash you do not control. That is a much more serious weakn
by throwaway2048 6y ago
because you can create two hashes that match, but you cannot create a hash that matches an arbitrary hash you do not control.
That is a much more serious weakness called a "second pre-image attack"
- deleted 6y ago[deleted]
- sedatk 6y agoSo, as I understand, that's expected to happen in foreseeable future. Otherwise, why switch from SHA1 if you can't create a collision with unaltered data?
- throwaway2048 6y agoIt is not expected to happen in the foreseeable future, MD5 for instance hasn't broken in a second pre-image way, more than a decade after it was known to be weak. This class of attacks is MUCH harder to construct against a cryptographic hash.
- sedatk 6y agoThen, why did BitTorrent work on such a costly change if it's not vulnerable against it?
- C4stor 6y agoFor the purpose of operating a bait and switch on the files, the torrent creators controls the two hashes somewhat, so it's an easier to pull attack.
- sedatk 6y agoIf you have control over the bait, I don't understand the reason to switch at all. Just make the bait evil and be done with it?