2 ms·
Hey, if you guys are working on this, check out these papers on SHA1 collisions: generated in 2^39 perms - http://www.cs.cmu.edu/~dbrumley/srg/spring06/sha-0.p
by brianliu 17y ago
Hey, if you guys are working on this, check out these papers on SHA1 collisions:
generated in 2^39 perms - http://www.cs.cmu.edu/~dbrumley/srg/spring06/sha-0.pdf http://www.cs.cmu.edu/~dbrumley/srg/spring06/sha-0.pdf
generated in 2^52 perms - http://eprint.iacr.org/2009/259.pdf http://eprint.iacr.org/2009/259.pdf
Since it would take an average supercomputer 5-6 days to generate the collision, I think I'm going to give the contest a rest (generating something close isn't useful outside the contest).
Another way to go about this is to sort huge rainbow tables by distance, which have been already created by a few reverse hash lookups ( http://md5.rednoize.com/ http://md5.rednoize.com/ , http://hashcrack.com http://hashcrack.com, http://sha1-lookup.com http://sha1-lookup.com ) - You'll probably need to contact them directly or hurry up and make your own.
Here's the SHA1 algorithm itself for anyone interested:
(Google Cache) http://74.125.95.132/search?q=cache:QjZpAaNXJr0J:https://www.reverse-engineering.net/viewtopic.php%3Ff%3D6%26t%3D1208+reverse+sha-1&cd=10&hl=en&ct=clnk&gl=us http://74.125.95.132/search?q=cache:QjZpAaNXJr0J:https://www...
- moonpolysoft 17y agoThose papers reference a collision attack, which is not the same thing as the point of this contest. The papers describe ways to generate pairs of messages that will hash to the same value. The contest describes a preimage attack, where one has a hash value and must guess an input which would have generated that hash. SHA-1 has no known preimage vulnerabilities, so the contest winner will either have to be lucky or break SHA-1. The best advice would probably be to iterate the keyspace in a novel way and hope you happen upon a good match that someone else doesn't get.