Kalmarunionen is a Capture The Flag (CTF) team within cybersecurity. We hack stuff and this is our website. Occasionally we also post writeups and tutorials on how we solved different cybersecurity challenges. You can always check our world ranking here.

Writeup by: andyandpandy, Anakin Solved by: Fr3d, c3lphie, Anakin, andyandpandy, patriksletmo, ly4k and more Writeup This challenge took us 21 hours to solve. Only 3 out of 524 teams solved it. Overview The challenge included a scenario where we had arbitrary javascript execution on a website. From here we were able to …

Revver, Midnight Sun CTF writeup Solved by: zzz, Zopazz Writeup by: Zopazz Description: Automated reversing is a solved problem, right. Writeup General challenge information In this challenge we were provided with a netcat session, which would respond with one of 20 random dynamically generated shellcodes encoded as …

kgbfskfsb, MidnightSun CTF writeup Writeup by: Nigma, nrabulinski Solved by: sebastianpc, Eldar Zeynalli (Hako), nrabulinski, Nigma Description: DeNiS Sergeev wants a secret mission payload… Attachments: kgbfskfsb.tar.gz The challenge description pretty clearly hints towards DNS stuff and sure enough, after …

Writeup by: Oliver Lyak (ly4k) Solved by: Zopazz, Oliver Lyak (ly4k) QLaaS QLaaS (Qiling as a Service) was a Clone-and-Pwn challenge with difficulty Schrödinger (whatever that means). The challenge was solved by 23 out of 947 teams. We are provided with the following attachment: …

Writeup by: Nicolai Søborg Solved by: Nicolai Søborg, Rasmus Have This year we managed to land a 13 place, again! (which is really a shame as top 12 gets swag …) Secured Java The challenge is a single python file that allows you to “run untrusted Java in a safe way”. The code boils down to: you …

Writeup by: Zanderdk | linkedin Solved by: ZZZ | linkedin, N00byedge | linkedin Indie VMM - HXP 2021 In this challenge we are given a root access to a linux machine running in the linux tools hypervisor and the goal is to escape out of the hypervisor to access the flag file on the host system. During this challenge we …

Writeup by: andyandpandy Solved by: andyandpandy, Hako Writeup The challenge has a race condition vulnerability, where you can delete your user and rapidly after send another request for the flag, which is successful when timed correctly. Description Web challenge Challenge author: pspaul/SonarSource To keep track of …

Writeup by: andyandpandy Solved by: andyandpandy, eskildsen, 2by4 Writeup This is most likely an unintended solution. TL;DR: Create a note with two iframes. First iframe gets /s/secret-note, second gets from evil.com, which returns a html page where another iframe is loaded based on an 0-day …

Writeup author: Bawstaws The Lost Bottle is the most awesome pirate game. It is about a young pirate, that lost her favorite bottle of old rum. She is now doomed to drink ordinary rum until she finds her bottle. Flags: 2531.00 Tags: rev, misc, game Introduction After discovering that this is a game challenge I quickly …