Sekai CTF 2022 : Symbolic Needs 1 & 2
A linux memory forensics challenge in two parts.
Angstrom CTF 2022 : CaaSio PSE
A js jail escape challenge. I learnt quite a few weird js techniques when solving this question.
Cybrics CTF 2021: localhost
Most of the CTF web challenges work on the Application layer. This is the first time I have encountered one that works on the Network layer. It’s quite an inspiring challenge.
The logic behind matrix diagonalization with eigenvectors
Diagonalization has a really close relationship with eigenvectors - the standard steps in diagonalizing a matrix is to find the eigenvalues with an eigenbasis. It first seemed like magic to me before knowing why this works. In this post, I’ll try to explain the rationale behind with the concept of linear transformation with two approaches: similarity diagram and matrix. The former one is a derivation oriented on the whole basis and linear transformation landscape, and the latter is merely a verification of correctness based on pure matrix multiplication mechanics.
Securinet CTF 2021 : Hack the Empire
Package managers are wonderful solutions to dependency issues, and they provide a simple interface for developers to install libraries. But what’s working behind when you’re typing that pip, npm, ..? This cool challenge highlights some of the potential pitfalls due to misconfigurations.