March 2017 archive

0CTF 2017 Quals – Zer0llvm

Talent Yang loves to customize his own obfuscator. Unfortunately, he lost his seed when he was watching Arsenal’s UEFA game. What a sad day! His team and his seed were lost together. To save him, could you help him to get back his seed? We can not save the game, but we may be able …

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0CTF 2017 Quals – OneTimePad 1 and 2

I swear that the safest cryptosystem is used to encrypt the secret! Well, maybe the previous one is too simple. So I designed the ultimate one to protect the top secret! Summary: breaking a linear and an LCG-style exponential PRNGs.

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33C3 CTF 2016 – beeblebrox (Crypto 350)

Make bad politicians resign! nc 2048 files Summary: factorization-based attack on a signature method

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