Boston Key Party CTF 2016 – Feistel (Crypto 5pts)

feistel – 5 – 15 solves : crypto: I just made a brand new cipher! Can you recover the key? feistel.go Summary: slide with a twist attack


PlaidCTF 2014 wheeeee writeup

Although it seems like The Plague’s messaging service is secure, there are bound to be bugs in any 20th century crypto system. We’ve recovered a version of the block cipher The Plague implemented. Use their online encryptor tool, at, to break the cipher and figure out Plague’s secret plans. NOTE: When the service sends… Continue reading »