The Photo Engine (Media Organizer & Lightroom) WordPress plugin before 6.6.0 does not have proper authorization checks when updating post data through one of its REST API routes in all versions up to, and including, 6.5.8. This makes it possible for authenticated attackers, with Author-level access and above, to modify the title, content, excerpt and other fields of arbitrary posts, pages and attachments, including those belonging to other users.