11-20.7z Info

: Extract the hidden flag from a series of nested or obfuscated archives. Step 1: Initial Reconnaissance

import subprocess import os filename = "11-20.7z" while True: # Attempt to extract. -p can be used if there's a known password. result = subprocess.run(["7z", "x", filename, "-y"], capture_output=True) # Logic to find the next .7z file in the directory next_files = [f for f in os.listdir('.') if f.endswith('.7z') and f != filename] if not next_files: break filename = next_files[0] print(f"Extracted: filename") Use code with caution. Copied to clipboard

: Use a Python script or a bash loop to extract until no more archives remain. 11-20.7z

Many "nested zip" challenges use a pattern where the filename itself is the key.

Once you reach the final file (e.g., 20.7z or a flag.txt inside it), the flag is rarely in plain text. Common obfuscations include: : Extract the hidden flag from a series

If "11-20" implies a range, this file likely contains 12.7z , which contains 13.7z , all the way to 20.7z or flag.txt .

: If you see a string ending in = , it's likely Base64. result = subprocess

The flag usually follows a specific format, such as CTF... or flag... . : CTFn3st3d_z1ps_4r3_fun_12345