URL Preview <= 1.0 - Unauthenticated Server-Side Request Forgery via 'url' Parameter

The URL Preview plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 1.0 via the 'url' parameter. This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.