What is CVE-2026-25420?

CVE-2026-25420 is a medium-severity vulnerability in Mailerlite, classified under Missing Authorization. CVSS score: 4.3/10. Published 2026-02-19.

How severe is CVE-2026-25420?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Mailerlite

CVE-2026-25420

Missing Authorization vulnerability in MailerLite MailerLite official-mailerlite-sign-up-forms allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects MailerLite: from n/a through <= 1.7.18.

Vulnerability class: Broken Access Control

EPSS: 0.002 (15.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

Affected products

Mailerlite — versions 0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

audit@patchstack.com (vdb-entry)

Frequently asked questions

What is CVE-2026-25420?: CVE-2026-25420 is a medium-severity vulnerability in Mailerlite, classified under Missing Authorization. CVSS score: 4.3/10. Published 2026-02-19.
How severe is CVE-2026-25420?: Medium severity. CVSS v3 base score is 4.3 out of 10.