Tag: linear

0CTF 2018 Quals – zer0SPN (Crypto 550)

0ops SPN, hope you enjoy it:) zer0SPN.zip Summary: linear cryptanalysis on toy block cipher

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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! oneTimePad.zip Well, maybe the previous one is too simple. So I designed the ultimate one to protect the top secret! oneTimePad2.zip Summary: breaking a linear and an LCG-style exponential PRNGs.

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Boston Key Party CTF 2016 – HMAC-CRC (Crypto 5pts)

[3] : hmac_crc – 5 – 36 solves : crypto: We’re trying a new mac here at BKP—HMAC-CRC. The hmac (with our key) of “zupe zecret” is ‘0xa57d43a032feb286’. What’s the hmac of “BKPCTF”? hmac-task.py Summary: breaking HMAC-CRC (again)

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