2 months ago
- The article describes solving a reverse engineering challenge from Google's Beginner CTF involving a binary exploitation and understanding assembly code.
- Challenge 1 exploited a path traversal bug to read the flag via /proc/self/cwd/flag after discovering the vulnerability through patchnotes.
- Challenge 2 required bypassing a secondary login by inputting a 35-character string, then XORing the stored binary flag data with 0xc7 to reveal the actual password.
- The writeup emphasizes the use of GDB for reverse engineering and analyzing the binary's assembly code to understand program logic.
- Tools like nc, GDB, and Python were utilized to interact with the remote service, debug the binary, and decrypt the flag.