CVE-2026-4561

medium

Description

The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the form response message post meta fields (e.g., 'text_subscribed', 'text_error') in all versions up to, and including, 4.12.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/641b739d-f888-4327-b1c5-c95de39ee011?source=cve

https://plugins.trac.wordpress.org/changeset/3491781/

https://plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/includes/forms/class-form.php#L295

https://plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/includes/forms/class-form-manager.php#L104

https://plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/includes/forms/class-form-element.php#L116

Details

Source: Mitre, NVD

Published: 2026-08-22

Updated: 2026-08-22

Risk Information

CVSS v2

Base Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.4

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Severity: Medium