rabbithole.md

Tenable 2021 CTF Rabbit Hole

This was fun.

Basically you start by navigating to the start page. This has some text like shown below.

You drop that code back into the url and it navigates to the next. This keeps going until eventually it just has end.

Now what do you do with the text?

I realized it look like an index and a hex, so I tested that. My code below inserts all values into a dictionary, then outputs them all in the end. It creates a hex file first then converts it to a byte file. Here's what you get:

Happy hacking!

page = 'http://167.71.246.232:8080/rabbit_hole.php?page='
cur = 'cE4g5bWZtYCuovEgYSO1'

import requests
import collections

c = {}

first = cur
r = requests.get(page+cur)
t = r.text

def process(c):
 out = ""
 for _ in range(max(k for k, v in c.items())+1):
  if _ in c:
   out += c[_]
 open('rabbithole.hex','w').write(out)

while t != 'end':
    var = t.split()
    c[int(var[0][1:-1])] = var[1][1:-2]
    cur = var[2]
    r = requests.get(page+cur)
    t = r.text

process(c)
open('rabbithole.png','wb').write(bytes.fromhex(open('rabbithole.hex','r').read()))