CVE-2025-61676: October CMS October

Medium severity, CVSS 4.8. EPSS: 0.3% chance of exploitation in the next 30 days.

October is a Content Management System (CMS) and web platform. Prior to versions 3.7.13 and 4.0.12, a cross-site scripting (XSS) vulnerabilities was identified in October CMS backend configuration forms. A user with the Customize Backend Styles permission could inject malicious HTML/JS into the stylesheet input at Styles from Branding & Appearance settings. A specially crafted input could break out of the intended <style> context, allowing arbitrary script execution across backend pages for all users. This issue has been patched in versions 3.7.13 and 4.0.12.

Affected products

• October CMS October: before 3.7.13 (fixed in 3.7.13); from 4.0.0, before 4.0.12 (fixed in 4.0.12)

Published 2026-01-10. Last modified 2026-06-17.