The Qi Blocks plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.4.9 via the 'page_id' parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with author-level access and above, to modify the stored Qi Blocks styles of arbitrary posts, templates, or widgets they do not own — including site-wide surfaces via the reserved 'template' and 'widget' page_id values — enabling unauthorized frontend defacement, content hiding, and degradation of any page on the site. The endpoint's permission_callback checks only the generic edit_posts and publish_posts capabilities, meaning any user with the built-in Author role satisfies the check regardless of post ownership.

The Qi Blocks plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.4.9 via the 'page_id' parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with author-level access and above, to modify the stored Qi Blocks styles of arbitrary posts, templates, or widgets they do not own — including site-wide surfaces via the reserved 'template' and 'widget' page_id values — enabling unauthorized frontend defacement, content hiding, and degradation of any page on the site. The endpoint's permission_callback checks only the generic edit_posts and publish_posts capabilities, meaning any user with the built-in Author role satisfies the check regardless of post ownership.