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Cryptax

This website is personal and does not represent my employer

Blog

CTFs and AI

CTFs and Artificial Intelligence. Post Ph0wn 2026 Thoughts. Myth #1: “CTF players hate AI because it spoils CTFs” Reality: this is not the opinion of the majority of CTF players “AI has destroyed CTFs” - this kind of message is frequent on the net. However, in a feedback form of Ph0wn CTF 2026, 80% hold no grudge against AI and are either happy with it, or just want to adapt:

Reviewing the AI-generated submissions with AI

Reviewing the AI-generated submissions with AI I am a reviewer for several conferences, and you won’t be surprised to hear we are getting an increasing number of AI-generated submissions with close to 0 technical value. I don’t know yet if those are (1) pure spam, or (2) naive authors who hope to get selected. Why should I spend human brains and time on something which was generated in seconds by AI?

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Write-ups

THCon 2026 - Forensics Challenges

Don’t forget to lock This is the first challenge of the Forensics category. 1 We seized a suspect's computer and managed to capture a RAM dump before it was powered off, along with an encrypted disk. Your objective is to decrypt the drive. We get a chall.tar.gz Solving the challenge The tar.gz contains 2 files: an ELF and a raw: 1 2 3 drwxr-xr-x aurel/aurel 0 2026-03-09 16:46 files/ -rw-r--r-- aurel/aurel 1072693248 2026-03-09 16:46 files/disk.

OSINT Industries Christmas 2025 CTF

OSINT Industries Christmas 2025 CTF Find the Masked Man Description In this first challenge, a photograph was taken on December 3rd, 2023 around 18:00 and we must identify the nearest metro station in Paris. We also get a hint that the scene is located near the intersection of a Rue and an Avenue. Solution I crop on the part of the image that shows shops. I can distinctively read “Julien”, and then perhaps “Brasserie” or “Creperie” or something like that, and a shop name ending “Aid” (maybe an English name).

XMas Root Me 2025

Xmas Root Me CTF 2025 X-Mas Assistant Day 1 Description of the challenge “Meet your X-Mas Assistant! It will help you throughout this entire month of CTF, providing a brand-new way to interact with CTFd through a “futuristic” Chatbot UI. This assistant talks directly to the CTFd API for you! Try it now! Can you exploit its MCP quirks and uncover the flag? This is not a web challenge.Meet your X-Mas Assistant!

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