The software that our company builds just went through a security audit. The auditors flagged our use of MD5 for hashing passwords that users can set if they want a password on their files. Having looked in to it, it seems that I should replace it with PBKDF2.
But to remove all MD5 hashing methods from the software this will mean users will need to temporarily lose all their passwords? As in, we will need to communicate to customers that if they update, all their files will not be password protected? I mean, I can check that an old hash exists and force them to manually set a new password but the password could be set by anyone which seems like kind of a big flaw. If an attacker has access to their file and the new version of our software, they will get access to the file with out password.