# Tag Info

Because MD5 has a 128 bit output, we knew up front that we could find an MD5 collision by simply hashing $2^{64}$ values; with that many values, we're likely to see the same output twice (Birthday Paradox). Today, $2^{64}$ would not be considered sufficient; there are currently large entities that could perform that much work, if it was important enough. ...
Basically all hash functions have this "problem". Pretty much all are finite in length. The real problem happens when collisions can be generated in less work than brute force. Due to the birthday problem with an $n$-bit hash function we would expect to see a collision after computing $n/2$ digests. If $n$ is large enough (say $n=160$) we would not expect ...