CVE-2026-3551

MEDIUM EPSS 28.0%
Published Apr 16, 20262mo ago · Modified Jun 17, 20262w ago
4.4 CVSS 3.1
Medium
Find Similar
Published Apr 16, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

Description

The Custom New User Notification plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's admin settings in all versions up to, and including, 1.2.0. This is due to insufficient input sanitization and output escaping on multiple settings fields including 'User Mail Subject', 'User From Name', 'User From Email', 'Admin Mail Subject', 'Admin From Name', and 'Admin From Email'. The settings are registered via register_setting() without sanitize callbacks, and the values retrieved via get_option() are echoed directly into HTML input value attributes without esc_attr(). This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in the plugin settings page that will execute whenever a user accesses that page. This could be used in multi-site installations where administrators of subsites could target super administrators.

CVSS Details

Base Score
4.4
Exploitability
1.3
Impact
2.7
Vector string
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N
Attack Vector Network
Attack Complexity High
Privileges Required High
User Interaction None
Scope Changed
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
28.0% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-79 Cross-site Scripting Injection

References 17

  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L132
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L46
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L52
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L59
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L84
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L90
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L97
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/custom-new-user-notification.php#L63
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L132
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L46
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L52
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L59
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L84
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L90
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L97
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/custom-new-user-notification.php#L63
  • wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/7a14d35d-144c-4ddd-b288-5e0e006fb165?source=cve

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.