[tudorconstantin]

Confession time: i still have some apps with salted md5 hashed passwords

[Cyranix]

The first step is accepting that you have a problem. Fortunately, it's fairly straightforward to fix the problem!

Previous discussion of how to handle this scenario: https://news.ycombinator.com/item?id=2689149

[thirsteh]

You shouldn't be using any of the functions on that page directly, anyway: http://throwingfire.com/storing-passwords-securely/#notpassw...

[zanny]

But it does matter, because if you can exploit a weakness in the hash function you can figure out the salt, strip it, and then use your precomputed dictionary.

[thirsteh]

That's not really how it works. Either way, you shouldn't be using just a regular "hash function" anyway. Even basic constructions like PBKDF2 use HMAC constructions where SHA1 and even MD5 are still pretty safe to use (although not very computationally expensive.)

[nly]

So migrate? Hash the hashes with Bcrypt or PBKDF2.

Bcrypt(MD5(password)) is just as effective as Bcrypt(password) at knocking brute force attempts on the head.

[finnw]

Unless the Bad Guys already have the MD5 hashes

[Xylakant]

Then the problem is not "I support an app that uses md5 hashes" any more. Your problem in that case is "all my users accounts were broken."

[nly]

Right, but you can still perform the migration I suggested and flag accounts for a password reset on next login.

[tacticus]

I was supporting an installation with md5 unsalted passwords

let us hang our heads in shame.