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Capture The Evidence v2 - June 2026 French gendarmerie 🇫🇷 organized a special CTF called “Capture The Evidence” from June 5 to June 15, 2026.
I participated for the first time, with a team of 4 called Eternal Green. The name of our team is a play on words based on Eternal Blue, the organizing team where blue is the color of the gendarmerie, and Green in our case in reference to the (famous?
Back from Auvergn’hack 2026 Auvergn’hack is a recent, local security conference in Clermont Ferrand (France). It is rather small: a single day and a single track, but it was a great discovery with an excellent ratio of interesting talks.
Yes, when you’re a “senior” with “20+ years of experience” (a kinder way of saying you’re old), you’ve already seen quite a lot. You don’t say it too often not to sound old and grumpy, but you are often disappointed with talks because they tell a story so similar to one you’ve already heard in the past.
CTFs and Artificial Intelligence. Post Ph0wn 2026 Thoughts. Update May 26, 2026:
Link to feedback from NorthSec CTF Update May 19, 2026:
Re-phrased first paragraph. In particular, replaced the title “Myth #1 CTF players hate AI [..]” with “CTF players hate AI [..]: True or False?” because I found my title was too biaised. It did not express fairly enough the reality. Added a paragraph on my (current) opinion. Added references to foreman, Kabir and Sthack CTF My opinion, in short The “problem” of AI in CTFs is very complex, with pros and cons…
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Write-ups
Auvergn’hack 2026 CTF: Crypto - Saki There was a crypto challenge at Auvergn’hack. I can’t remember exactly the title (I think it was “Saki” or something). I did not preserve the description either, but the only important files that were provided were:
an encrypted message (message.txt): 1 {"h": "g1oatFTHSYsUH377iZQSuesUM/t+pFXRrwCrNW8v8Lw=", "n": "WQq7B4XEueM=", "m": "2gFQlO5+YZFnqaar7QEGpu3/f/2WdbJEWPnVjNuNs2dXyHUi7/8="} a verification file (v.txt), with a single word: Monkey a Python script (script.py) to encrypt or decrypt messages Goal: we need to decrypt message.
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 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).
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