NuttyShell CTF 2025: memo-ry
I played NuttyShell CTF 2025 organized by the Hong Kong Polytechnic University, and came across siunam’s web challenges. In particular, memo-ry is a hard challenge that required players to chain multiple vulnerabilities to retrieve the flag. I found it really fun and decided to compile a writeup for this.
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BlazCTF 2024 Writeup
This time I went to @DeFiHackLabs and attempt my very first Web3-focused CTF. I am fortunately able to solve some challenges. Nothing particular difficult, but that's still something.
Read More →HITCON CTF 2024 Writeup
The crypto challenge authors in HITCON 2024, @maple3142 and @_bronson113 prepared a set of exciting and difficult challenges. I collaborated with @thehackerscrew1 as a guest player this time. In this blog post, we will cover three challenges: ZKPoF, PCBC Revenge and Hyper512.
Read More →Google CTF 2024 (III): IDEA
IDEA is a challenge written by @0xdeuterium. He even provided me the paper to refer, my only contribution to the challenge is to optimize the original solution so that we don’t need 65K-ish oracle calls.
Read More →Google CTF 2024 (II): ZKPOK
ZKPOK is a challenge I made while learning Zero Knowledge Proofs on zk-learning.org. I was watching the first lecture video, I came across with the interactive proof for quadratic residues at 20:00. This made me ponder - it should be easy to apply Fiat-Shamir transform to make this non-interactive. Let’s also use MD5 so that it could be vulnerable. Hours later, this challenge appeared without a proper solve script.
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