Tag: lcg

Polictf 2017 – Lucky Consecutive Guessing (Crypto)

We implemented a random number generator. We’ve heard that rand()’s 32 bit seeds can be easily cracked, so we stayed on the safe side. nc lucky.chall.polictf.it 31337 chall.py Summary: breaking truncated-to-MSB LCG with top-down bit-by-bit search.

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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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Google CTF – Woodman (Crypto 100)

How honest are you? Running here Summary: breaking a weak PRNG

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Gits 2012 #14 Pwnable (300)

Jacked file running at jacked.final2012.ghostintheshellcode.com:2121 Summary: weak random, BlackJack bot, format string

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