Writeups from Capture the Flag (CTF) events I participated in. About web, scripting, crypto, reversing and everything in between. All writeups include detailed explanations of how everything works.

Hacky Holidays Unlock the City 2022

An almost 3 week long CTF with beginner to hard challenges. Very high quality challenges with every week a new batch of challenges to try.

Challenge the Cyber 2022

A Dutch CTF event with a Training Mission to practice, and a real CTF after. Part of the European Cyber Security Challenge. The challenges were all high quality and good learning material

NahamCon CTF 2022

A yearly Capture The Flag event that was a part of NahamCon. The event lasted 48 hours, and had loads of challenges from different categories.

Cyber Santa is Coming to Town 2021

A 5-day long CTF, with a challenge of every category coming out every day. Challenges range from beginner to medium.

Google Beginners Quest 2021

A CTF hosted by Google, with some beginner/medium challenges

Cyber Apocalypse 2021

22 April is International Earth Day and guess what… The Earth was hacked by malicious extraterrestrials. Their ultimate plan is to seize control of our planet. It's only you who can save us from this terrible fate.