Tags: hash-collision rc4 crypto 

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The core of this problem is to take an IV first 32 bytes of an RC4 keystream, and construct a password that when prepended to this IV is able to generate the same first 32 bytes of keystream.

Solving it required analyzing RC4 and coming up with such an algorithm.

Original writeup (https://4cad.github.io/CTF_Writeups/201910%20BalsnCTF/Harc4/Balsn%20CTF%202019%20-%20Harc4%20%20Challenge.html).