exFAT extra long file path

Version

Date	Author	Contact	Version	Comment
23/10/2019	noraj (Alexandre ZANNI)	noraj#0833 on discord	1.0	Document creation

Information

Information displayed for CTF players:

• Name of the challenge / Nom du challenge: The long way
• Category / Catégorie: Misc
• Internet: not needed
• Difficulty / Difficulté: easy / facile

Description

You need to go deeper...
But when you'll be deep the dark will surround you...

Flag format: sigsegv{flag}

author: [noraj](https://pwn.by/noraj/)

Hints

• Hint1: It's a scripting challenge right?
• Hint2: exFAT
• Hint3: buffer

Integration

Just share the .img file.

Solving

Author solution

1. Identify the file system type of the .img: exFAT
2. Mount it
3. See there is a folder in a folder in a folder...
4. See that all folders are numbers: int (hex) -> str (chr) gives a valid ASCII value
5. Retrieve the complete path and transform it to ASCII text

In order to accomplish step 5 you will need to script because the path is way too long, so ls or general library filesystem helpers can't handle it. You have to take a bufferized approach.

solve.sh is automating steps 1. to 5.

Flag

sigsegv{noooo0000000oooo0000000000oooooooo000000000000000ooooooOOOOOOOOOOOOOOOOo_liimit!}

SigSegV2

A misc challenge that was available during SigSegV2 CTF (2019).

20 teams on 36 flaged this challenge.