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.

Read More →
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 →
HKCERT CTF 2022 Postmortem (III): The Remaining Challenges

In the last part, I will include the two non-crypto challenges I wrote for HKCERT CTF 2022: Numbers go brrr and Minecraft geoguessr.

Read More →
HKCERT CTF 2022 Postmortem (II): Harder Crypto Challenges

We will continue walking through the remaining crypto challenges I wrote for HKCERT CTF 2022: Mystiz can't code, Slow keystream and King of Rock, Paper, Scissors.

Read More →
HKCERT CTF 2022 Postmortem (I): Easier Crypto Challenges

This is the third year Black Bauhinia co-organized HKCERT CTF. This time I wrote nine challenges: Seven crypto, one reverse and one misc. Similar to the last year, I have a series of three blog posts walking through the challenges that I wrote. We will discuss the four easier crypto challenges: Flawed ElGamal, Catch-22, Rogue Secret Assistant and Base64 encryption.

Read More →
← Younger Posts Older Posts →