HKCERT CTF 2023 Postmortem (II): Harder Crypto Challenges
In the second part of the series, I will cover four cryptography challenges: baDES, Maybe Someday, Cipher Bridging Service and RSA Triooo. Interestingly, most of them are somehow "plagiarized" from the other CTFs.
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HKCERT CTF 2023 Postmortem (I): Easier Crypto Challenges
This is yet another moment that Black Bauhinia co-organizes HKCERT CTF. This year, I am slightly more productive than the previous years and wrote 13 challenges for the CTF. There are three blog posts in this series, where I will respectively cover the author’s solutions to the easier crypto challenges, the harder crypto challenges and the remaining challenges.
Read More →Firebird CTF 2024: Goldilocks
This is yet another annual Firebird CTF and I only wrote one cryptography challenge this time, Goldilocks. There were one solve (out of 53 participating teams) during the contest period.
Read More →DownUnderCTF 2023 Writeup
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.
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Bauhinia CTF 2023: How to Stop Time
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.
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