Smart Custom Fields <= 4.2.2 - Missing Authorization to Authenticated (Subscriber+) Post Content Disclosure

The Smart Custom Fields plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the relational_posts_search() function in all versions up to, and including, 4.2.2. This makes it possible for authenticated attackers, with subscrber-level access and above, to retrieve post content that is password protected and/or private.