Execute me if you can

ringzer0ctf

Task: a web endpoint serves a fresh x86-64 shellcode blob per request and demands its output within ~1s on the same session. Solution: statically analyze the shellcode (it writes the bitwise NOT of a 12-byte data blob located after the call opcode e8 ae ff ff ff), compute the answer without emulation, and submit it on the same cookie jar inside the time window.