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Group 42-Sells Out! - The Information Archive
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Group 42 Sells Out (Group 42) (1996).iso
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crypto
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crack
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wincrack
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wincrack.txt
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1994-06-28
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901b
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16 lines
The PC DOC program WINCRACK "cracks" file enciphered by the utility
WINCRYPT. WINCRYPT is described in "WinCrypt Protects Your Data" by Jeff
Prosise starting on page 361 of the July 1994 issue of PC Magazine (Volume 13
Number 13).
Essentially, WINCRYPT implements a Vigenere cipher (using exclusive-or
instead of modular addition) with a 512 byte key. Thus, every 512-th byte
of enciphered text is enciphered in the same Caesar alphabet. For each of the
512 Caesar ciphers, WINCRACK finds the enciphered value of the most frequent
plaintext character. Given a very frequent plaintext character (e.g., space
in a text file), this allows most of the Caesar alphabets to be recovered;
most of the plaintext is then recovered.
For example, using the attached files, "WINCRACK TEXT.ENC TEXT.DEC 32"
will yield TEXT.DEC -- a recognizable version of the cryptography FAQ.