MacKrack is a freeware password hash brute forcer for Mac OS X, supporting the Crypt, MD5 and SHA-1 algorithms. It has two modes: dictionary and keyspace brute force. It also features Mac OS X password extraction, for 10.2 and 10.3 passwords. Version 1.3 supports dictionary/brute force attacks against .dmg image files, dictionary appending, customizable character set bruteforcing, and Estimated Time Remaining.