CVE-2026-15052

HIGH

The MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Form Field Values in all versions up to, and including, 4.3.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

CVSS v3.1 Score

7.2
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Published: 8/1/2026Modified: 8/3/2026

Related Intelligence (1)

HIGHVulnerability

NVD HIGH: CVE-2026-15052 — The MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builder plugin ...

The MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Form Field Values in all versions up to, and including, 4.3.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesse

CVE-2026-15052
NIST NVD

References (7)

https://plugins.trac.wordpress.org/browser/mailchimp-subscribe-sm/tags/4.3.3/admin/classes/ajax-requests-class.php#L1224https://plugins.trac.wordpress.org/browser/mailchimp-subscribe-sm/tags/4.3.3/admin/classes/ajax-requests-class.php#L2311https://plugins.trac.wordpress.org/browser/mailchimp-subscribe-sm/tags/4.3.3/admin/classes/ajax-requests-class.php#L906https://plugins.trac.wordpress.org/browser/mailchimp-subscribe-sm/tags/4.3.3/integrations/form-builder-database/extension.php#L127https://plugins.trac.wordpress.org/browser/mailchimp-subscribe-sm/tags/4.3.3/integrations/form-builder-database/extension.php#L179https://plugins.trac.wordpress.org/changeset?reponame=&old=3627272%40mailchimp-subscribe-sm&new=3627272%40mailchimp-subscribe-smhttps://www.wordfence.com/threat-intel/vulnerabilities/id/c3d2425e-69e5-4efe-bbc6-0ef121e74341?source=cve