CVE-2026-4056

The User Registration & Membership plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the Content Access Rules REST API endpoints in versions 5.0.1 through 5.1.4. This is due to the `check_permissions()` method only checking for `edit_posts` capability instead of an administrator-level capability. This makes it possible for authenticated attackers, with Contributor-level access and above, to list, create, modify, toggle, duplicate, and delete site-wide content restriction rules, potentially exposing restricted content or denying legitimate user access.

The following products are affected by CVE-2026-4056 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-4056.

URL	Resource
https://plugins.trac.wordpress.org/browser/user-registration/tags/5.1.1/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php#L116
https://plugins.trac.wordpress.org/browser/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php#L116
https://plugins.trac.wordpress.org/changeset/3485702/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php
https://www.wordfence.com/threat-intel/vulnerabilities/id/7bb5a5a2-9644-4850-a5f9-7c925af000c8?source=cve