CVE-2026-16149 PUBLISHED

Security Hardener <= 2.4.4 - Authenticated (Subscriber+) Privilege Escalation via REST API '/wp/v2/users' permission_callback Overwrite

Assigner: Wordfence
Reserved: 17.07.2026 Published: 22.08.2026 Updated: 22.08.2026

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>. Because the block_user_enum option defaults to enabled, no special plugin configuration is required — the overwrite is active on every request as soon as the plugin is installed.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 8.8

Product Status

Vendor marc4
Product Security Hardener
Versions Default: unaffected
  • affected from 0 to 2.4.4 (incl.)

Credits

  • zickzick2 finder

References

Problem Types

  • CWE-269 Improper Privilege Management CWE