note iburrell You are missing the point of the attack. One of the main properties of a cryptographic hash is that is hard to FIND a collision. There are certainly collisions, but with a secure hash function and a large enough size, it is practically impossible to find another input that produces the same hash. This is very important for many cryptographic protocols. <p> This attack takes finding an MD5 hash collision from difficult brute force to relatively easy. This doesn't matter too much for many uses of MD5 where security isn't important. 386193 386470