FILE UPLOAD ATTACKS: Blacklist Filters

HTB Content Academy
28

I hope you have completed this task. Anyway, I will give you some tips to complete this task.

Steps:

  1. Identify the blacklisted extension; the section itself provides a wordlist; feel free to use any of them.

  2. Identify the allowed extension and save the result for your location.

  3. Upload the script to any one of the allowed extensions, visit that location, and execute it. Since it does not display anything, we have to find which one executes on the server.

  4. Capture the request and send it to the intruder; choose the allowed extension wordlist that you have saved.

  5. cmd=id: check which extension has executed on the response.

3 Likes
29

This is the best advice to get you through

30

Very useful! thank you.

31

You don’t have to use the the GET request. Using the Post request would work just fine

32

This would work perfect. As for those that are yet to solve this. Do more research on what file extension would execute a php code. ChatGPT would help.