When I left my last position, my friends and colleagues with whom I’ve worked for years gave me a little challenge: a PDF with a hidden ciphertext. At first I had to use Excel to decipher the ciphertext, but later I wrote a small Python tool to help me.
The simple ciphers supported by this tool are XOR, ROT, Vigenère and subtract (I added that last one because it was used in a maldoc). You can use the man page (option -m) to learn more.
cipher-tool_V0_0_1.zip (https)
MD5: B7D44090A76F66D7194D0A0D890E2CEB
SHA256: 1E8E1F112595FC08C3C20A06D172C21DDE6375EC8651A8DE6EF57B938F3E67E8
Didier Stevens 
Hi Didier, a few years ago I wrote a similar tool (bbtrans) as part of the balbuzard project. I made it modular so that it should be easy to add more transforms.
bbtrans: https://bitbucket.org/decalage/balbuzard/wiki/bbtrans
Available transforms: https://bitbucket.org/decalage/balbuzard/wiki/Transforms
Comment by decalage0 — Tuesday 22 November 2016 @ 9:58
Nice!
Comment by Didier Stevens — Tuesday 22 November 2016 @ 10:01
[…] Didier Stevens has released a deciphering Python script that supports “XOR, ROT, Vigenère and subtract”. Simple Ciphers: cipher-tool.py […]
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