https://app.hackthebox.com/challenges/210

Description

Give me the key and take what’s yours.

Exploitation

#!/usr/bin/python3

a = ['H', 'T', 'B']
b = [0x3f, 0x64, 0x35]
xor = [chr(ord(a[i]) ^ b[i]) for i in range(3)]
key = ''.join(xor)
print(key)

run the program and send the result to retrieve the flag.

Summary

Baby Crypt: recover the XOR transform from the binary and invert it to reveal the flag.