Possibly truly stupid question, but what is the attack on md5ing passwords if yo... | Hacker News

Hacker Newsnew | past | comments | ask | show | jobs | submit

		sunir on June 11, 2009 \| parent \| context \| favorite \| on: Cryptographic Right Answers Possibly truly stupid question, but what is the attack on md5ing passwords if you also generate a random salt for each user? I could not find anything online in the past ten minutes that suggests an attack, except for the md5 collision problem. I don't understand the collision problem very well either. I know it's been used to crack a certificate here or there, but it seems like it took a lot of resources to crack one password.

tptacek on June 11, 2009 | [–]

http://www.matasano.com/log/958/enough-with-the-rainbow-tabl...

sunir on June 15, 2009 | | [–]

Thomas, thanks. That was immensely helpful. Now I have to figure out what I want to do going forward. At least I already have per-user random salts.

jameskpolk on June 11, 2009 | [–]

The collision problem is a huge deal. You can no longer trust a MD5 signed object.

http://www.mscs.dal.ca/~selinger/md5collision/ has some great, and very scary examples.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact