Blog & Career Highlights
Welcome to my blog where I document important milestones in my cybersecurity journey — from organizing CTFs and delivering workshops to participating in conferences and specialized trainings.
Each post is listed in reverse chronological order
Career Timeline
🟩 2025-09-11 – Sekurak Hacking Party @ PJATK
Participated in the Sekurak Hacking Party hosted at PJATK Warsaw.
Engaged in hands-on cybersecurity labs, network exploitation challenges, and live demonstrations of real-world attack scenarios presented by experienced security professionals.
🟩 2025-06-15 – JWT Security Presentation
Delivered a 60-minute presentation titled “JWT Security Deep Dive” to the PJATK Security Research Club (~60 attendees).
Discussed token manipulation, signature bypasses, and mitigation strategies.
🟩 2025-06-08 – Co-organizing PJHACK 2025 CTF
I co-organized PJHACK 2025, a Capture The Flag competition with over 40 participants.
I created 3 original challenges (Web, Reverse Engineering, and OSINT) and managed Docker-based infrastructure for the event.
Read more about the event
🟩 2025-05-16 – Attending KPMG App Security Training
I participated in hands-on workshops focusing on OWASP Top 10 vulnerabilities, secure coding practices, and red teaming exercises.
This training helped sharpen my practical web application testing skills.
Stay Connected
Thank you for following along on my journey in cybersecurity, CTFs, and professional growth.
I regularly update this blog with new writeups, event summaries, and reflections on my projects.
If you’d like to stay in touch or collaborate:
- 📨 Email: oskar.biernacki.it@gmail.com
- 💼 LinkedIn: linkedin.com/in/oskarbiernacki
- 🐙 GitHub: github.com/OskarBiernacki