L0phtCrack is a password auditing and recovery application (now called LC5), originally produced by Mudge from L0pht Heavy Industries. It is used to test password strength and sometimes to recover lost Microsoft Windows passwords, by using dictionary, brute-force, and hybrid attacks. It was one of the crackers' tools of choice, although most use old versions because of its price and low availability.
The application was produced by @stake after the L0pht merged with @stake in 2000. @stake was acquired by Symantec in 2004. Symantec has since stopped selling this tool to new customers citing US Government export regulations, and has announced that they will discontinue support by the end of 2006. The product, however is still available for download via 'you-know-what' :p
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