5 ms·
SHA and MD are fast hashers. You want slow hashers for password security like b-crypt and s-crypt.
by kaiju0 6y ago
SHA and MD are fast hashers. You want slow hashers for password security like b-crypt and s-crypt.
- dheera 6y agoDoesn't PBKDF2 fix that as long as you use a very large number of irritations?
- sneak 6y agoIn theory, absolutely. In practice, bitwarden's server limits the max iteration count on a user account to something that remains insecure. They refuse to fix it. https://github.com/bitwarden/server/issues/589 https://github.com/bitwarden/server/issues/589
- Shoop 6y agoWhat do you think about this reply on that thread? https://github.com/bitwarden/server/issues/589#issuecomment-751418282 https://github.com/bitwarden/server/issues/589#issuecomment-...
- batrat 6y agoFor me is not a big deal. If your password is Hunter22 than you have bigger problems than PBKDF. It doesn't matter if they PBKDF it 30 milion times. Longer passwords are harder to crack and I still don't understand why people not using passphrases in their passwords. Having 2fa enabled on all other accounts it makes me sleep better if somehow one day BW or any other password manager gets compromised.
- Harvesterify 6y agoUse a longer and more complex master password. You're welcome.
- sneak 6y agoYou're the sixth person to reply to me with this "advice". My own password is 30 characters and I self-host bitwarden_rs, patched to permit a higher KDF iteration count. This has nothing to do with my usage.
- the_mitsuhiko 6y agoEvidently there is no problem then.
- luis8 6y agoIs sharing you password length wise? Knowing the # of chars you have reduced the number of iterations needed to complete a brute force attack. 255! vs 255! / (255 - 30)! My math could be off though, i haven't work with factorials since i was in the university
- throwaway744678 6y agoIt's a trick. OP's password is actually 29 chars long, but the attacker will now start at 30 characters, and never brute force the actual password. Nicely played.
- Dylan16807 6y agoI don't think you want a factorial involved. With unknown size, cracking 30 characters takes time proportional to n^30 + n^29 + n^28 etc. Cracking just 30 is proportional to n^30. The difference is negligible. A percent or two.
- luis8 6y agoMy bad, I was thinking in permutations but those does not allow repeated entries. It make sense now, like you said the difference is negligible.
- user5994461 6y agoPBKDF2 is a slow algorithm specifically created for password hashing. It's in the same family as bcrypt and scrypt.
- px43 6y ago> PBKDF2 is a slow algorithm specifically created for password hashing. Yeah, over 20 years ago. It's woefully out of date by modern standards. PBKDF2 doesn't even attempt memory hardness, so there are whole classes of attacks on later generation slow hashing algorithms that don't even apply to PBKDF2 because of how old it is. Argon2 is extremely resistant to Time-Memory-Trade-Off (TMTO) attacks, which older algorithms like bcrypt and scrypt are vulnerable to. PBKDF2 is essentially a linear slowdown, which is effectively pointless these days.
- user5994461 6y agoMath doesn't age. Cheers. bcrypt and scrypt, the successors to PKDF2, are both more than a decade old. RSA is half a century old and it's still up to date by modern standards. In fact nobody has came up with anything better. Edit: Actually, bcrypt might be as far as 1999, possibly older than PBKDF2.
- goalieca 6y ago> RSA is half a century old and it's still up to date by modern standards. In fact nobody has came up with anything better. RSA is currently a minefield of gotchas and few security companies even get it right. Just generating a good key is actually a very difficult task. It is also very computationally slow and has many practical issues for the level of security it provides. There are many superior replacements in both pqc and elliptic spaces. I would take EdDSA over rsa-pss any day of the week.
- user5994461 6y agoRSA is extremely simple, it's just multiplications and powers. It can be reasonably explained to high school students. The tooling is mature and keys are trivial to generate safely with a openssl command. EdDSA is another level entirely. I don't know how you can recommend elliptic curve cryptography with a straight face if you think RSA is hard. P.S. It's a myth that EdDSA is faster. This depends on operation (signing vs verification) and key size.