21 de maio de 2025 · 3208 palavras · 16 minutos · CTF Reversing Crypto
More than one month has past since DEF CON Quals, but we were so exhausted by it only now we managed to put together this set of write-ups. This year, several CTF-BR affiliated teams united to form pwn de queijo (a pun with pão de queijo). Together, we managed to achieve top17, the best position achieved by a Brazilian team until now. Let’s keep training to get qualified to the Finals next year :D
12 de maio de 2025 · 3692 palavras · 18 minutos · CTF Reversing
This past weekend (05/09-05/11), we participated in DamCTF 2025, organized by the Oregon State University Security Club. On this writeup, first we will focus on two reverse engineering challenges: ‘Is it data or data?’ and ‘It’s data, not data’. They’re both related, in that they’re two different versions of a similar ‘game’, albeit with different rules and possible commands. You could say ’not data’ is a sequel to ‘or data?’, especially since the CTF admins recommended playing one after finishing the other.
15 de abril de 2025 · 3030 palavras · 15 minutos · CTF Reversing Hardware
It has been a few weeks since we played WolvCTF 2025, but I’ve been longing to write about LockDown, a simple but fun hardware reverse engineering challenge. The problem statement follows: I’m trying to use this adder, but I can’t figure out what password gets it to work. Can you figure it out? NOTE: to get the flag, convert the password bit-string into an ASCII string, with password[47] as the MSB and password[0] as the LSB.