Oskar Biernacki

Welcome to my website where I share my journey in cybersecurity, record my learnings, and explore various topics.

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Writeups & CTF Walkthroughs

Here you can find my detailed writeups for CTFs and selected cybersecurity challenges. Each entry links to a separate page containing the full walkthrough, code, diagrams, and exploit analysis.

Writeup List

Title Platform Short Description Link
Gatekeeper TryHackMe Step-by-step guide showing how to solve the buffer overflow challenge and capture the flag. view
LazyAdmin TryHackMe Walkthrough of the LazyAdmin machine: enumeration, exploitation, and privilege escalation. view
onigirico TryHackMe Full walkthrough: enumeration, cookie-based login bypass, and LFI exploitation to capture the flag. view