users who used FileVault prior to http://www.engadget.com/2012/02/01/mac-os-x-10-7-3-released/ may be able to find their password in a system-wide debug log file, stored in plain text outside of the encrypted area. This puts the password at risk of being read by other users or enterprising cyber criminals, Emry explains, and even opens the door for new flaw-specific malware.
Seems Apple took some cues from Sony.
