The Rate Star Review Vote - AJAX Reviews, Votes, Star Ratings plugin for WordPress is vulnerable to Missing Authorization in all versions up to and including 1.6.4. The vwrsr_review() AJAX handler lacks both capability checks and nonce verification. The only access control is an is_user_logged_in() check. When the 'form' parameter is set to 'update', the function takes an arbitrary post ID from the user-supplied 'rating_id' GET parameter, sets it as the post ID in the update array, and passes it directly to wp_update_post(). This overwrites the target post's title, content, author (changed to the attacker's user ID), post_type (changed to the plugin's custom post type, default 'review'), and status. Additionally, update_post_meta() is called on the arbitrary post ID at lines 758-763, modifying its metadata. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify the title, content, author, post type, and metadata of arbitrary posts and pages on the site via the 'rating_id' parameter, effectively allowing full post content takeover.