XSS in Automatic.css
CVE-2026-15273
The Automatic.css plugin for WordPress is vulnerable to Stored Cross-Site Scripting via REQUEST_URI in all version 4.0.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts that will execute whenever an administrator accesses the Activity Log settings page.
Vulnerability class: XSS (Cross-Site Scripting)
Published .
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Automatic.css — versions 4.0.0
Weakness classification (CWE)
References
- www.wordfence.com/threat-intel/vulnerabilities/id/07d697c5-1c15-4d3a-8637-cc4fd…
- plugins.trac.wordpress.org/browser/automaticcss-plugin/trunk/classes/UI/Setting…
- plugins.trac.wordpress.org/browser/automaticcss-plugin/trunk/classes/Helpers/Lo…
- plugins.trac.wordpress.org/browser/automaticcss-plugin/trunk/classes/Plugin.php
- plugins.trac.wordpress.org/browser/automaticcss-plugin/trunk/classes/Lib/WideEv…
- automaticcss.com/changelogs/
Frequently asked questions
- What is CVE-2026-15273?
- CVE-2026-15273 is a medium-severity vulnerability in Automatic.css, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-09-26.
- How severe is CVE-2026-15273?
- Medium severity. CVSS v3 base score is 6.4 out of 10.