Part. 3 - sudo python

Category: WEB - Points: 220 - Solves: Description: Find a way to elevate the privileges of the current user. This step is the result of a three-part challenge. It is reset every 30min, so the platform may be unavailable for a few seconds. Link : https://web3.hackday.fr/

Solution: To solve this challenge you need to find a way to control the server and find the flag. The vulnerability was found in the Part. 1 - Uploads and the shrek user password was found in the Part. 2 - Old md5. To find the the third (and last) flag we need to find a way to become root with a Python command. Before, we've seen that shrek user isn't a root user but he can execute bash commands. So with some researches, we found that the os module can help us to execute machine commands. After some trials, the command to become root is : sudo python3.5 -c 'import os; os.system("/bin/bash")' With this command we become root and we can see the /root folder content. This folder contain the FlaG3.txt so we have the flag.

🚩 FLAG

  HACKDAY{987oiuhgfytrJGFUYTR152649}