There are a lot of ups and downs for in 2023. There were some joyful gatherings and reunions, but at the same time, things did go very wrong.

The crypto challenges in DownUnderCTF are very intriguing. Unfortunately I have very limited time during the contest and could only solve apbq rsa ii (26 solves), hhhhh (14 solves) and handshake (4 solves). I will be covering the latter two challenges in this writeup.

After four years of team formation, we organized our first edition of Bauhinia CTF last weekend. There are over 650 teams registered and over 200 teams scored. This year, I made one crypto challenge, How to Stop Time. I also coauthored a web/crypto challenge, Amnesia, with @chthollic_.

This post is served as a short writeup of How to Stop Time, a crypto challenge with six solves during the contest period.

MHK2 is one of the challenges I coauthored for Google CTF 2023 and there were 18 teams solving this challenge during the contest time.

Asian Cyber Security Challenge (ACSC) is an annual CTF where players are competing individually, and the best young Asians will be selected form a team to represent Asia to compete with others. I ended up winning the competition among 450+ players. Unfortunately, I am unable to qualify because of the age and nationality conditions.

In this blog post, I will cover two web challenges, @t0nk42’s easySSTI (43 solves) and @tyage’s Gotion (9 solves).