Media Cleaner: Clean your WordPress! <= 7.0.3 - Authenticated (Administrator+) Server-Side Request Forgery

The Media Cleaner: Clean your WordPress! plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 7.0.3. This is due to the `get_urls_from_html()` function using `DOMDocument::loadHTMLFile()` to fetch iframe source URLs with an insufficient hostname validation check that relies on a substring match against the site's server name. This makes it possible for authenticated attackers, with Administrator-level access and above, to make web requests to arbitrary locations originating from the web application, which can be used to query and interact with internal services.