2023 ImaginaryCTF - chaos

• Points: 100

Description

Can you find order in the midst of chaos?

Attached

chaos.py

Solution

By allforest01

from math import exp, log

code = open("chall.py").read()
inp_str = "\\x36\\x39\\x20\\x36\\x65\\x20\\x37\\x30"
ans = [0 for i in range(51)]
pos = 0
while True:
    pos = code.find(inp_str, pos)
    if pos == -1:
        break
    pos = code.find("__getitem__(", pos) + len("__getitem__(")
    nxt = code.find(")", pos)
    ans_pos = eval(code[pos:nxt])
    pos = code.find("__pow__(", pos) + len("__pow__(")
    nxt = code.find(")", pos)
    ans_pow = int(code[pos:nxt])
    pos = code.find("__eq__(", pos) + len("__eq__(")
    nxt = code.find(")", pos)
    ans_equ = int(code[pos:nxt])
    ans[ans_pos] = chr(round(exp(log(ans_equ) / ans_pow)))

for i in ans:
    print(i, end='')
print()

The flag is

ictf{pYthOn_obFuScAtION_iS_N0_M4TCH_f0r_U_9e1b23f9}