02 - Project Chimera
Draft completePublished draft: Python bytecode extraction, decompilation, and final ARC4 decryption.
Overview
Project Chimera is a multi-stage encrypted Python challenge. Rather than trying to read the packed program directly, I extracted the staged contents into .pyc files and loaded them into PyLingual for a decompiled view.
Stage one
The first decompiled stage decodes a Base64 payload, decompresses it with zlib, unmarshals the resulting Python code object, and executes it. That established the next stage of the challenge.
Stage two
The next .pyc exposed the important logic: it constructs a user signature, compares it with the lead-researcher signature, and uses the matching value as the ARC4 key for the encrypted formula.
Final solve
I recreated the relevant checks in a small helper: derive the expected researcher identity, set it as the current user, rebuild the signature, and decrypt the formula with ARC4.
Running that path prints the final flag.
