CTF

This weekend I played my first CTF of the year : the 0XFFUN CTF. I actually only played for some hours but managed to solve two “hard” challenges Warden and 67 Revenge :) This is my writeup for 67 Revenge TLDR Vulnerability Leak Heap and Libc Heap Spray House of Einherjar Leak Stack Ropchain While the challenge was ranked as hard on the CTF, it’s a fairly standard heap challenge exploitation where I got stuck mainly because someone that will recognise himself told me consolidation was impossible on strange things and stuff that shows my lack of recent practice on heap exploits. ...

This year, I solved my first challenge from a big CTF. The challenge was fpon and involved manipulating FSOP for RCE. For this challenge a Dockerfile and the binary were provided. I first extracted the ld and libc from the Docker and used pwninit to have a fpon_patched running with the correct ld and libc, as exploits can work differently if not using the correct version. Now that we are all setup we can look at the challenge. ...