RE: Password Cracking Challenge...

> From: David Riley [mailto:oscar@the-rileys.net]
> Sent: Monday, July 28, 2003 4:47 PM
>
> It is a good starting point, and that's what I thought of as well.

That, plus the fact that the first 8 bytes of the hashes for "Password123" and "Password321" are the same, suggests to me a 64-bit block cipher running in some chaining mode. DES in CBC mode, for example.

The fact that all the hashes are 128 bits would suggest that the algorithm either discards characters after the 16th, or perhaps that it uses the first and last block of cipher output as the hash (which would be a little better). It'd be nice to have two sample vectors of 17-byte passwords, only differing in the 17th byte, to check.

I'll leave further speculation to the actual cryptanalysts (assuming any of them find this sufficiently interesting to bother).

-- 
Michael Wojcik
Principal Software Systems Developer, Micro Focus