PWN Racecar challenge — HTB

Format string vulnerability [x32]

This is a re-uploaded article from years ago. HTB banned it because the challenge was still active. I promised the audience to re-upload it after the challenge is retired.

This is my 5th writeup referring to the methodology described here.
It will be as always:

• concise,
• straight to the point.
• without the steps that lead to the rabbit hole.

0. Download the binary:

Source: https://app.hackthebox.eu/challenges

1. Basic checks:

2. Spot the vulnerability — format string:

• Format string vulnerability lies in the printf() after “winning the race”.