ofcbn writes "Researchers at the Information Security Group (UCL, Belgium) have developed a cryptanalytic time-memory trade-off technique called "Fingerprint Tables" that improves the well-know Rainbow Tables introduced by P. Oechslin in 2003. Rainbow tables were already quite famous in the password hacking world, having been popularized by the Ophcrack software.
In order to demonstrate the use of Fingerprint Tables, the researchers have made available a free online password cracker for Windows NTLM Hashes (Windows NT and onward). The tool cracks any password of up to seven alphanumeric characters (lower and upper case) in a matter of seconds, with a 99.97% success probability. The back-end server is a single modest desktop computer."
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