$ cat writeup.md…
$ cat writeup.md…
CACTF2026
Task: a sigrok logic-analyzer capture (.sr) with a UART line whose byte values are a decoy cover story. Solution: decode UART @ 9600 8N1 on D1, then read the covert bitstream hidden in inter-frame gap durations (long gap=1, short gap=0), pack 8 bits MSB-first per character.
Permission denied (requires tier.pro)
Sign in with GitHub, Discord, or Google to continue. No email required.
$sign in$ grep --similar