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.
https://github.com/inc2734/smart-custom-fields/commit/67cb6d75bd8189668f721dbd2dc7a3036851be1b