3 ms·
How is the lack of a salt the problem? AFAIK, all salts do is head off rainbow table attacks. If you're using SHA1 and you lose the passwords, a salt isn't goin
by chc 14y ago
How is the lack of a salt the problem? AFAIK, all salts do is head off rainbow table attacks. If you're using SHA1 and you lose the passwords, a salt isn't going to help you, because they don't need to rainbow table you — they can use a dictionary attack or just brute force the passwords without much trouble.
It seems to me that losing the passwords was the real problem, and it's compounded by a poor choice of hashing algorithm and lack of a salt. Lack of a salt is not good, but I don't see how it's worse than losing them in the first place. If they'd used bcrypt or not lost the passwords, a rainbow table wouldn't be useful in the first place.
- akkartik 14y agoI don't understand your line of reasoning. Aren't rainbow tables just another kind of brute force attack? They just allow you to share the brute force across a large number of passwords. Salts increase the effective length of the password, and per-password salts eliminate rainbow tables and make brute forcing harder as well. What am I missing? --- Linkedin now says their passwords are salted, so we could change our passwords now even if I was right. But they're also claiming that all passwords are now salted. http://blog.linkedin.com/2012/06/06/linkedin-member-passwords-compromised http://blog.linkedin.com/2012/06/06/linkedin-member-password... In any case, I'm enjoying this conversation, thanks.
- whichdan 14y agoI wonder how they're salting their current database. sha1(sha1(pass) + salt)?
- akkartik 14y agoHere's a far better response: http://queue.acm.org/detail.cfm?id=2254400 http://queue.acm.org/detail.cfm?id=2254400