https://ur4ndom.dev Cryptography, CTFs, and more en https://ur4ndom.dev/static/avatar.png https://ur4ndom.dev https://ur4ndom.dev/posts/2024-03-18-breakfaest I heard that you could use VOLE-in-the-head to make post-quantum signatures. Here's a signature scheme based on the Poseidon hash function. Can you create a forgery? Mon, 18 Mar 2024 20:00:00 +0100 https://ur4ndom.dev/posts/2024-03-18-breakfaest Robin Jadoul vole-in-the-head crypto zero-knowledge fiat-shamir https://ur4ndom.dev/posts/2024-02-26-lattice-training A training for team Europe, getting in shape for the next edition of the ICC. Mon, 26 Feb 2024 18:00:00 +0100 https://ur4ndom.dev/posts/2024-02-26-lattice-training Robin Jadoul lattice presentation training icc team europe https://ur4ndom.dev/posts/2024-02-11-dicectf-quals-diligent-auditor I hired an auditor to secure my python interpreter! Sun, 11 Feb 2024 15:00:00 +0100 https://ur4ndom.dev/posts/2024-02-11-dicectf-quals-diligent-auditor Robin Jadoul dicectf misc pyjail https://ur4ndom.dev/posts/2023-07-02-uiuctf-vimjail Four jails were made for the king of editors, one exploit to rule them all. Sun, 02 Jul 2023 23:01:00 +0200 https://ur4ndom.dev/posts/2023-07-02-uiuctf-vimjail Robin Jadoul uiuctf misc jail vim https://ur4ndom.dev/posts/2023-07-02-uiuctf-rattler-read All these poisonous snakes keep biting me. Good think I remembered to bring restrictedpython to keep me safe! Sun, 02 Jul 2023 23:00:00 +0200 https://ur4ndom.dev/posts/2023-07-02-uiuctf-rattler-read Robin Jadoul uiuctf misc pyjail https://ur4ndom.dev/posts/2022-07-04-gctf-cycling Pack out your quantum computer and perform 2^1025-3 encryptions to solve this challenge. Good luck doing this in 48h. Tue, 05 Jul 2022 18:42:00 +0200 https://ur4ndom.dev/posts/2022-07-04-gctf-cycling Robin Jadoul gctf organizers crypto RSA factoring https://ur4ndom.dev/posts/2022-07-04-gctf-treebox I think I finally got Python sandboxing right. Mon, 04 Jul 2022 19:06:00 +0200 https://ur4ndom.dev/posts/2022-07-04-gctf-treebox Robin Jadoul gctf organizers misc pyjail https://ur4ndom.dev/posts/2022-02-08-dicectf-ti1337 Back in the day the silver edition was the top of the line Texas Instruments calculator, but now the security is looking a little obsolete. Can you break it? Tue, 08 Feb 2022 20:52:00 +0100 https://ur4ndom.dev/posts/2022-02-08-dicectf-ti1337 Robin Jadoul dicectf organizers misc pyjail https://ur4ndom.dev/posts/2022-02-08-dicectf-typed ~~Haskell~~ Rust is a dynamically typed, interpreted language. Can you get my code to stop erroring? Tue, 08 Feb 2022 00:56:00 +0100 https://ur4ndom.dev/posts/2022-02-08-dicectf-typed Robin Jadoul dicectf organizers rev rust https://ur4ndom.dev/posts/2021-12-13-seccon-signwars A long time ago in a galaxy far, far away.... Mon, 13 Dec 2021 16:31:06 +0100 https://ur4ndom.dev/posts/2021-12-13-seccon-signwars Robin Jadoul seccon organizers crypto ECDSA lattice mt19937 https://ur4ndom.dev/posts/2021-06-01-intigriti-xss-0521 🤖 Are you a robot? Our intern built this handy captcha to find out! Tue, 01 Jun 2021 00:00:00 +0000 https://ur4ndom.dev/posts/2021-06-01-intigriti-xss-0521 Robin Jadoul intigriti XSS web https://ur4ndom.dev/posts/2021-05-01-ictf-apr-2021 Sat, 01 May 2021 00:00:00 +0000 https://ur4ndom.dev/posts/2021-05-01-ictf-apr-2021 Robin Jadoul ImaginaryCTF challenges crypto misc pyjail web reversing https://ur4ndom.dev/posts/2021-04-01-ictf-mar-2021 Thu, 01 Apr 2021 00:00:00 +0000 https://ur4ndom.dev/posts/2021-04-01-ictf-mar-2021 Robin Jadoul ImaginaryCTF challenges crypto misc pyjail https://ur4ndom.dev/posts/2021-03-01-ictf-feb-2021 Mon, 01 Mar 2021 00:00:00 +0000 https://ur4ndom.dev/posts/2021-03-01-ictf-feb-2021 Robin Jadoul ImaginaryCTF challenges web https://ur4ndom.dev/posts/2021-01-22-mathemagic Debunking crackpot claims for fun and profit Fri, 22 Jan 2021 20:00:00 +0200 https://ur4ndom.dev/posts/2021-01-22-mathemagic Robin Jadoul RSA crypto fun https://ur4ndom.dev/posts/2020-12-07-pbctf-gcombo One day I spied out my friend accessing some google form to enter his secret combination lock. Afterwards, I kept bothering him about it, and he finally decided to give the link to me. Maybe you can figure out his combo for me and get a tasty flag in return Mon, 07 Dec 2020 16:31:08 +0100 https://ur4ndom.dev/posts/2020-12-07-pbctf-gcombo Robin Jadoul pbctf organizers misc google forms graph https://ur4ndom.dev/posts/2020-12-07-pbctf-sploosh I wanted to make my own URL scraper, but parsing HTML is hard, so I used some random open source scraping project instead. Mon, 07 Dec 2020 16:31:07 +0100 https://ur4ndom.dev/posts/2020-12-07-pbctf-sploosh Robin Jadoul pbctf organizers web SSRF https://ur4ndom.dev/posts/2020-12-07-pbctf-r0bynotes Rails is secure by default so it's perfect for my amazing notes app Mon, 07 Dec 2020 16:31:07 +0100 https://ur4ndom.dev/posts/2020-12-07-pbctf-r0bynotes Robin Jadoul pbctf organizers web ruby filter bypass deserialization https://ur4ndom.dev/posts/2020-12-07-pbctf-leak I know there's a famous attack on biased nonces. Then, how about this? 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