Writeup of the crypto-challenge MonoDOOM ETERNAL from #KalmarCTF - A follow up from last-years MonoDOOM challenge, this time with botched side-channel protection!

jonathke.github.io/monoDOOM-ETE...

#KalmarCTF is currently well underway - and we’re once again featuring prizes sponsored by @hex-rays.bsky.social and Zellic !

Come play along by visiting kalmarc.tf

Using SonarQube to solve a CTF challenge? Done! ✅

Learn how we detected a 0-day vulnerability during #KalmarCTF, making us first to solve the challenge! From Zip Slip to RCE, using lazy class loading:

www.sonarsource.com/blog/code-se...

#appsec #CTF #vulnerability

Jonathan Komada Eriksen - Notes

GG everyone who played #KalmarCTF 2025!

Writeups for my two challs:

MonoDOOM: jonathke.github.io/monoDOOM
A chal based on a sick sidechannel attack by @damienrobert.bsky.social !

Not-so-complex multiplication: jonathke.github.io/not-so-complex
An easy chal based on complex multiplication.

With under 48 hours till we kick off with #KalmarCTF 2025, we are happy to announce that Zellic is joining as a sponsor this year, as well as an updated prize pool!
Come compete with the best competitive hackers from around the world!

Registrations are now open at kalmarc.tf !