# Bytecode — License Validator (CTF challenge)

> A vendor shipped only the compiled Python bytecode (.pyc) of their license validator — no source. The valid license key is the flag, stored XOR-encoded. Reverse the bytecode to recover it.

Canonical: https://codelivly.com/ctf/challenges/re-python-bytecode

| | |
|---|---|
| Category | Reverse Engineering |
| Difficulty | Medium |
| Points | 400 |
| Estimated time | 20 min |
| Type | Live instance |
| Solves | 30 |
| Author | Codelivly |

A vendor shipped only the compiled Python bytecode (.pyc) of their license validator — no source. The valid license key is the flag, stored XOR-encoded. Reverse the bytecode to recover it.

## Related

- [All CTF challenges](https://codelivly.com/practice?type=ctf)