CVE-2026-3253: Mailerlite – Signup Forms Official

Medium severity, CVSS 4.3. EPSS: 0.2% chance of exploitation in the next 30 days.

The MailerLite – Signup forms (official) plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the forms() method of the AdminController class in all versions up to, and including, 1.7.21. This makes it possible for authenticated attackers, with Contributor-level access and above, to create or delete arbitrary signup forms.

Affected products

• Mailerlite Mailerlite – Signup Forms Official: up to and including 1.7.21

Published 2026-09-24. Last modified 2026-09-24.