Yoast SEO <= 26.5 - Insecure Direct Object Reference to Authenticated (Contributor+) Sensitive Information Exposure via 'post_id' Parameter

The Yoast SEO plugin for WordPress is vulnerable to Insecure Direct Object References in all versions up to, and including, 26.5. This is due to insufficient authorization checks in the Meta Search REST API endpoint that fail to verify post ownership. This makes it possible for authenticated attackers, with Contributor-level access and above, to read sensitive SEO metadata from any post on the site via the 'post_id' parameter, including posts owned by other users, private posts, and draft posts.