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Reverse engineeringmedium250 pts0 solves

License Check

A vendor "protects" its Python tool with home-made obfuscation. You have the script but not a licence key. Reverse it to get the activation code.

Learning objectives

Read and deobfuscate simple XOR-based checks; understand why client-side secrets are recoverable.

Instructions

Analyse license_check.py (do not just guess). You may run it, but the goal is to recover the key and the activation code by reading the code.

Prerequisites: Basic Python.
Flag format: cspk{...}
Files: license_check.py (0.8 KB) (download after registering)
Useful tools: Ghidra radare2
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References

Write-up

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