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⚙️Reverse EngineeringMedium 400 XP 30 solves 20 min
Bytecode — License Validator
by 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.
It is the compiled intermediate form Python generates from source, stored in .pyc files. The interpreter runs it, and analysts can disassemble it to understand program logic.
How can I inspect a .pyc file?
Use Python's dis module to disassemble it, or a decompiler such as uncompyle6 or decompyle3 where the version is supported, to recover readable source.
Is reverse engineering Python code hard?
It is gentler than native binaries because bytecode keeps structure. This medium challenge on Codelivly is free and a good first step into reverse engineering.