$ ctf42

Put_Down_Thy_Wrath

Crypto No technique tags yet.
Difficulty Not rated yet

Flag format: poctf{...}

In this challenge, you are given a public key and an encrypted message that was encrypted using a flawed implementation of homomorphic encryption. Your task is to analyze the encryption algorithm, identify its weaknesses, and use them to decrypt the message and reveal the flag. The provided file contains the encryption implementation, and here is the public key and the encrypted message. Good luck!

C: 79,74,3f,0f,5a,27,21,3a,36,48,64,51,64,0f,79,7e,1a,64,64,03,33,0f,64,64,57,21,27,3f,0f,2c,4a,3a,3f,24,27,3f,0f,7e,64,79,1a,64,2c

Public Key:

NOTE: A deployment error has rendered this challenge arbitrary. No modifications will be made to this challenge.

Right Click, Save As... Download Homomorphic Function MD5 checksum: 4AE1F620789BC30B12B520A8D7B0FB69

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