ProSolution WP Client < 2.0.9 - Subscriber+ SSRF via proSol_url_validate

The ProSolution WP Client WordPress plugin before 2.0.9 does not validate a user-supplied URL, and does not check the capability or nonce of the requester, before performing a server-side HTTP request with it, allowing any authenticated user, such as a subscriber, to make the site issue arbitrary requests to internal hosts and services, including requests with an attacker-chosen method, headers and body.