CVE-2026-3551
Vulnérabilité moyenne dans Custom New User Notification (rafasashi)
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.
Gravité et risque d'exploitation
CVE-2026-3551 obtient un score CVSS de 4.4/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.41 %, ce qui la place devant 34.0 % des CVE référencées.
Que faire ?
- Vérifiez si Custom New User Notification (versions <=1.2.0, 0) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://www.wordfence.com/threat-intel/vulnerabilities/id/7a14d35d-144c-4ddd-b288-5e0e006fb165?source=cve
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L46
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L46
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L52
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L52
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L59
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L59
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L84
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L84
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L90
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L90
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L97
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L97
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/admin/includes.php#L132
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/admin/includes.php#L132
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/trunk/custom-new-user-notification.php#L63
- https://plugins.trac.wordpress.org/browser/custom-new-user-notification/tags/1.2.0/custom-new-user-notification.php#L63
