Reverse Engineering

Reverse engineering is the process of gleaning implementation details from a black box. It is also a category of CTF challenge which involves tasks such as decompiling, understanding program logic, etc. Reverse is also one of the strongest UNO cards.

Reverse Engineering a Siemens Programmable Logic Controller for Funs and Vulns (CVE-2024-54089, CVE-2024-54090 & CVE-2025-40757)

When security by obscurity breaks...

2025‑09‑12

10 minute read

HKCERT CTF 2023 – Decompetition: Vitamin C++

A beginner-friendly writeup to reverse-engineering C++ a lá decompetition. Years of complex shenanigans condensed!

2023‑11‑16

11 minute read

_^N[Subtype Metaprogramming_^] is _^N[Mostly Harmless_^]

Inheritance go brrrrrrrr... abusing turing-complete typesystems to write fun programs in Python.

2023‑10‑02

12 minute read

HITCON 2023 – The Blade

Beginner-friendly writeup for a nifty Rust reversing challenge.

2023‑09‑20

12 minute read

GDB/GEF Cheatsheet

Quick command reference on one of the most powerful tools for dynamic analysis.

2023‑09‑11

7 minute read

DUCTF 2023 – Wrong Signal

You straight to oops(). Right away.

2023‑09‑04

3 minute read

HKCERT CTF 2022 – C++harming Website

A harming website? Hope it doesn't harm my sleep!

2022‑11‑15

5 minute read

DownUnderCTF 2022 – ezpz-rev

Grid puzzles aren't that easy.

2022‑09‑28

8 minute read

AOC 2021 Day 24 – No U

Finally a reverse engineering challenge in Advent of Code.

2022‑08‑25

6 minute read

TAMUctf 2022 – Labyrinth

Using CFGs to solve a control-flow maze.

2022‑04‑22