XSS in Mailerlite – Signup Forms (Official)

CVE-2025-13993

The MailerLite – Signup forms (official) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'form_description' and 'success_message' parameters in versions up to, and including, 1.7.16 due to insufficient input sanit…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (24.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-13993?
CVE-2025-13993 is a medium-severity vulnerability in Mailerlite – Signup Forms (Official), classified under Cross-site Scripting. CVSS score: 5.5/10. Published 2025-12-12.
How severe is CVE-2025-13993?
Medium severity. CVSS v3 base score is 5.5 out of 10.