Centralized Memory was a hard Linux pwn challenge created for the European Cyber Week CTF 2023 qualifiers. This write-up covers the intended method of exploitation through a race condition, an AES padding bug and a stack overflow.

kaleidoscope was a hard reverse engineering challenge created for the European Cyber Week CTF 2023 qualifiers, with a focus on Windows-specific mechanisms and VM-based obfuscation.

The Calculator in Shadow was a hard pwn challenge created for the European Cyber Week CTF 2023 qualifiers. It included exploiting a RISC-V calculator running on top of a customized QEMU that featured a poorly implemented shadow stack.