Addon Library <= 1.3.76 - Missing Authorization to Authenticated (Subscriber+) Arbitrary File Upload

The Addon Library plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the onAjaxAction function action in all versions up to, and including, 1.3.76. This makes it possible for authenticated attackers, with subscriber-level access and above, to perform several unauthorized actions including uploading arbitrary files.