[Digital Overdose CTF 2022] Lightning Seeds - CRYPTOGRAPHY

out.txt

encrypt.py

그럼 decrypt.py 프로그램을 만들어보자

 

import random

enc = bytes.fromhex(4fbac83555040313c4cc337d8d8da48351921dfb7cd47433857432c2ee665d821227)

for i in range(1000):
	random.seed(i)
    flag = ''.join(chr(c ^ random.radint(0,255)) for c in enc)
    if "DOCTF" in flag:
    	print(flag)
        break