Lepton's Crack is a generic password cracker, easily customizable with a simple plug-in system. It can perform a dictionary-based (wordlist) attack, as well as a brute-force (incremental) password scan.

For the incremental scan, the user can provide a regex-like expression that will be enumerated, thus checking every possible combination. This powerful feature effectively combines `shoulder-surfing' with standard brute-forcing.

By default it comes with the following modules:
* md4 : standard MD4 hash
* md5 : standard MD5 hash
* nt4 : NT MD4/Unicode
* dom : Lotus Domino HTTP password
* sha1 : standard SHA-1 hash
* null : trivial 1-byte hash