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.
References5
- plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/inclu…
- plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/inclu…
- plugins.trac.wordpress.org/browser/mailchimp-for-wp/trunk/inclu…
- plugins.trac.wordpress.org/changeset/3491781/
- www.wordfence.com/threat-intel/vulnerabilities/id/641b739d-f888…
Metrics
- CVSS 3.1
-
6.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 27 · as of 9 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.