4 ms·

> But SHA-1 is thoroughly deprecated, and will be broken in the next few years. Why is this a problem? sha1 is not broken by design, it's only broken by curren

• taejo 10y ago
  No, SHA-1's design is broken. The attacks still need a lot of computing power, but much less than they would if SHA-1 was secure.
• geofft 10y ago
  That's not true. SHA-1 is a 160-bit hash, which means that you'd expect it to take on average 2^80 hash computations to find a collision. The best attacks against full SHA-1 require more like 2^57 to 2^61 computations, and there are attacks against parts of SHA-1 that require quite a bit less than that (which indicates that the design is risky). https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_validation https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_valida... The difference between 2^60 and 2^80 is huge. If 2^80 operations take, say, a thousand years, it would take only about 8 hours to do 2^60 operations. (Also, there's the additional twist that SHA-1 isn't even the fastest known algorithm. If you switch to BLAKE2, you can get faster hashing, and the output is 256-bit, so the brute-force strength is 2^128, which more than makes up for each individual operation being a little faster. https://blake2.net/ https://blake2.net/)