BalsnCTF 2022 Writeup
vss is an interesting crypto challenge in BalsnCTF, which ended up having 9 solves. I took around 2.5 hours to solve the challenge. This challenge reminds me the yet another PRNG challenge from pbctf 2021, but with a setting which looked harder. I was pretty surprised that LLL worked, too. lfsr is another crypto challenge in BalsnCTF with 6 solves. In the challenge, the output bits are computed nonlinearly from the LFSR states. Given that I knew almost nothing about LFSR, I just came up with the attack by myself… Well, I am not quite a paper guy and I couldn’t read.
Read More →De1CTF 2019 Writeup
It has been a very long time that I've compiled a writeup. This time I have played on my own as @blackb6a. Let me write on some particular interesting ideas that I have learnt in the challenges. Bear with me if you find this writeup _too_ math-intensive. The solution scripts will be committed to my Github repository sooner or later, after I've managed to prettify them.
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