8.8
HIGH CVSS 3.1
CVE-2026-16149
Security Hardener <= 2.4.4 - Authenticated (Subscriber+) Privilege Escalation via REST API '/wp/v2/users' permission_callback Overwrite
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>. 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.

INFO

Published Date :

Aug. 23, 2026, 12:16 a.m.

Last Modified :

Aug. 23, 2026, 12:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-16149 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update the Security Hardener plugin to patch the missing authorization vulnerability.
  • Update the Security Hardener plugin.
  • Verify plugin settings after update.
  • Remove plugin if not needed.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-16149 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-16149 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-16149 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-16149 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 23, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'marc4', 'product': 'Security Hardener', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.4.4'}], 'defaultStatus': 'unaffected'}]
    Added 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>. 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-269
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L107
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L180
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L204
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L428
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L433
    Added Reference https://plugins.trac.wordpress.org/browser/security-hardener/tags/2.4.4/security-hardener.php#L439
    Added Reference https://plugins.trac.wordpress.org/changeset/3630896/security-hardener
    Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/64f1a71f-e210-4191-bfb4-56f8568180ed?source=cve
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.