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So I wanted to encrypt some files. Thought about using 7z+password. Stackexchange folks said "Didn't review it but it should be fine. You can browse the code yourself". So I did. After a few mins I noticed they use 8byte "random" IV. Yes, half of IV is zeroes. But it gets worse.
Aside from the fact that 7z XORs plaintext with zeroes, I was curious about the "RandomGenerator" which generates IV. That's when I vomited. The first comments say "This is not very good random number generator. Please use it only for salt." It is not used only for salt.
Yes, it uses PID and time(null) as seed. Yes, this is 7zip's random generation code running on your computers in 2019. More "cursed" code below. #7zip #encryption #facepalm #randomness #entropy #RNG #crypto #cryptofail 
