Basic SSRF against the local server

Description

This lab has a stock check feature which fetches data from an internal system.

Reproduction and proof of concept

1. Browse to /admin and observe that you can’t directly access the admin page.

2. Visit a product, click “Check stock”, intercept the request in Burp Suite, and send it to Burp Repeater.

3. Change the URL in the stockApi parameter to http://localhost/admin. This should display the administration interface.

4. Read the HTML to identify the URL to delete the target user, which is:

http://localhost/admin/delete?username=carlos

5. Submit this URL in the stockApi parameter, to deliver the SSRF attack.

Exploitability

An attacker will need to change the stock check URL to access the admin interface at http://localhost/admin and delete the user carlos.