Opal Membership <= 1.2.4 - Authenticated (Subscriber+) Information Disclosure

The Opal Membership plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 1.2.4 via the private notes functionality on payments which utilizes WordPress comments. This makes it possible for authenticated attackers, with subscriber-level access and above, to view private notes via recent comments that should be restricted to just administrators.