What is CVE-2026-1300?

CVE-2026-1300 is a medium-severity vulnerability in Mehtevas Responsive Header Plugin, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2026-01-24.

How severe is CVE-2026-1300?

Medium severity. CVSS v3 base score is 4.4 out of 10.

XSS in Mehtevas Responsive Header Plugin

CVE-2026-1300

The Responsive Header plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple plugin settings parameters in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (10.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N.

Affected products

Mehtevas Responsive Header Plugin — versions 0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

Frequently asked questions

What is CVE-2026-1300?: CVE-2026-1300 is a medium-severity vulnerability in Mehtevas Responsive Header Plugin, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2026-01-24.
How severe is CVE-2026-1300?: Medium severity. CVSS v3 base score is 4.4 out of 10.