| FPDTP |
2026-03-08 23:31 |
First writeup for this challenge
A full reverse engineering walkthrough of toasterbirb's FPDTP — a covert channel challenge where two binaries communicate by encoding messages into Unix file permission bits. Covers static analysis with strings/objdump, discovering the shared /tmp/fpdtp_pipe channel, building a real-time Python interceptor, and reverse engineering the nibble-split encoding scheme to decode the full conversation. No prior knowledge of covert channels required — everything is explained from scratch. |
| int overflow |
2026-03-06 10:18 |
Found one password. Then found infinite.
Complete walkthrough - Ghidra decompilation, live overflow observation in GDB registers, and a Python script that predicted and confirmed 10 valid passwords against the real binary. |