KOREONEMidnight Flag CTF 2026 – 😀 Challenge Writeup
This challenge presents an extremely restrictive C code jail. A remote server accepts a single line of C source code from the user, validates it against a character filter, compiles it with GCC using special flags (no libc, no standard startup code, static linking), and executes the resulting binary. The flag is stored at /flag-.txt on the filesystem. The core difficulty lies in the character filter:…
Midnight Flag CTF 2026 – 😀 Challenge Writeup » kore.one
This challenge presents an extremely restrictive C code jail. A remote server accepts a single line of C source code from the user, validates it against a character filter, compiles it with GCC using special flags (no libc, no standard startup code, static linking), and executes the resulting binary. The flag is stored at /flag-.txt