A powerful, flexible, and fast multi-platform password hash cracker. John the Ripper is a fast password cracker, currently available for many flavors of Unix, DOS, Win32, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types which are most commonly found on various Unix flavors, as well as Kerberos AFS and Windows NT/2000/XP LM hashes. Several other hash types are added with contributed patches.

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Latest Release:- John the Ripper 1.7
Download:- http://www.openwall.com/john/