tag: CyberApocalypse2021

Cyber Apocalypse 2021 5/5 - Artillery

28 Apr, 2021 by pistach3

Artillery was a web challenge of the Cyber Apocalypse 2021 CTF organized by HackTheBox. We were given the source code of the server to help us solve the challenge. This challenge was a nice opportunity to learn more about XXE vulnerabilities.

Cyber Apocalypse 2021 4/5 - Discovery

28 Apr, 2021 by Thalium team

One of the least solved challenges, yet probably not the most difficult one. It is a Hardware challenge, though it is significantly different from the other challenges of this category. The first thing to spot is that when starting the challenge machine, we have access to two network services:

  • an HTTP server, requesting an authentication
  • an AMQP broker, rabbitmq

Cyber Apocalypse 2021 3/5 - Off the grid

28 Apr, 2021 by Charles Paulet & Yoanne Girardin

Off-the-grid was the 4th hardware challenge of the Cyber Apocalypse 2021 CTF organized by HackTheBox. We were given an Saleae trace and schematics to analyse. Thalium was one of the very first of 99 players to complete it.

Cyber Apocalypse 2021 2/5 - Wii-Phit

28 Apr, 2021 by Colas Le Guernic

Wii-Phit was the only Hard crypto challenge designed by CryptoHack for the Cyber Apocalypse 2021 CTF (there were also 4 challenges categorized as Insane though).

There is already an excellent writeup by the challenge organizers: one could recognize a well known equation related to the Erdős–Straus conjecture, some participants used Z3. We took a different approach.

Cyber Apocalypse 2021 1/5 - PWN challenges

28 Apr, 2021 by Jérémy Rubert & Anonymous from Thalium team

Thalium participated in the Cyber Apocalypse 2021 CTF organized last week by HackTheBox. It was a great success with 4,740 teams composed of around 10,000 hackers from all over the world. Our team finished in fifth place and solved sixty out of the sixty-two challenges:


This article explains how we solved each pwn challenge and what tools we used, it is written to be accessible to beginners: