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# Full WriteUp
Full Writeup on our website: [http://www.aperikube.fr/docs/xiomara_2018_re1/](http://www.aperikube.fr/docs/xiomara_2018_re1/)

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# TL;DR

The binary is a .NET executable. We can easily extract source code with ILSpy.

The flag is ciphered with an XOR algorithm but key’s length is very small.

I wrote a small python script which performs a brute force attack to recover the flag.