CVE-2026-16149

Technical Description

The Security Hardener plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 2.4.4. The vulnerability exists because the plugin's user-enumeration protection, which is enabled by default, hooks the rest_endpoints filter via secure_user_endpoints() and overwrites every registered handler's permission_callback on both the /wp/v2/users and /wp/v2/users/(?P<id>[\d]+) routes — including POST, PUT, PATCH, and DELETE handlers — with a bare closure that returns only is_user_logged_in(), completely stripping WordPress Core's original capability checks such as create_users, promote_user, edit_users, and delete_users that WP_REST_Users_Controller normally enforces. This makes it possible for authenticated attackers with Subscriber-level access and above to create new Administrator accounts by sending POST request to /wp/v2/users with administrator role, or to reset an existing Administrator's password by issuing a PUT/POST request to /wp/v2/users/<id>. B

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References