RapidExpCart <= 1.0 - Stored XSS via CSRF

The plugin does not sanitize and escape the url parameter in the rapidexpcart endpoint before storing it and outputting it back in the page, leading to a Stored Cross-Site Scripting vulnerability which could be used against high-privilege users such as admin, furthermore lack of csrf protection means an attacker can trick a logged in admin to perform the attack by submitting a hidden form.

PoC

1. Save the following as .html file and open it in the browser where Administrator is logged in.