# Breaking decryption.ch: the CTF that wasn't meant to be

This article is a write up regarding the challenge published on decryption.ch by the Ex0-Sys company. Even if I resolved it in 2019, it took me a bit of time and motivation to write and finalize that blog post. Better late than never, as they say.

# Donjon CTF SSSGX write-up: linear functions strike back

This writeup presents a solution to the SSSGX Wallet stage of the 2020 Ledger Donjon’s CTF. It showcases a solution using a kind of generic method to exploit the issues that we are facing in this challenge, which can basically be reduced to solving a linear system in the vector space $$\{0,1\}^N$$.

# Lifting shared libraries & PIE binaries with DragonFFI (and LIEF)

Dragonffi 0.6.0 comes with new APIs that can be leveraged to call arbitrary functions within a shared library (or position independent (aka PIE) binaries).

# Emulating NotPetya bootloader with Miasm

NotPetya is a famous malware of the Petya family. It appeared in June 2017. The part running from the Master Boot Record (MBR) has been statically and dynamically studied, using for instance the Bochs debugger from IDA. Is another approach possible? This article’s goal is to show that we can emulate this bootloader using Miasm.