لاسبوع الجاي هنفتح بث نحل في ctfs من pico 🤍

تاريخ البث : يوم الجمعه الساعه 6 بتوقيت مصر

البث هيبداء الساعه 6 و عشر دقائق عبال ما ناس تصلي

طبعا هيكون الجمعه الساعه 6 بتوقيت مصر 🤍

Of course, it will be on Friday at 6 PM Egypt time 🤍

الحمدالله 🤍

سعيد جدا و فخور اني بشارك رايتب من اصعب رايتب الي موجودين علي منصه #flagyard الرايتب عباره عن تحدي كريبتو و حاليا مفيش غير 40 انسان حول العالم بس الي قدرو علي حل تحدي




I’m happy to share a new CTF write-up I’ve published on Medium :

“Reduced Collisions” 🧠🔐

In this challenge (Cryptography – FlagYard), I analyzed a custom hash function built on linear algebra and modular arithmetic, then exploited its structure to generate hash collisions.


🔍 What this write-up covers :


Reverse engineering the provided server-side cryptographic logic
Modeling the hash function as a linear system


Applying lattice reduction (LLL algorithm) to recover valid collision vectors

Crafting a working solution to obtain the flag

This challenge was a great exercise in combining theory (linear algebra & lattices) with practical exploitation, which is something I really enjoy about cryptography-focused CTFs.

📖 Full write-up :

https://spider1sec.medium.com/ctf-write-up-reduced-collisions-9373e48adc75

حد لاحظ اني نسيت اعمل بث ؟