CVE-2023-28819: Concretecms Concrete CMS

Medium severity, CVSS 5.4. EPSS: 0.6% chance of exploitation in the next 30 days.

Concrete CMS (previously concrete5) versions 8.5.12 and below, 9.0.0 through 9.0.2 is vulnerable to Stored XSS in uploaded file and folder names.

Affected products

• Concretecms Concrete CMS: before 9.1.0 (fixed in 9.1.0)

Published 2023-04-28. Last modified 2026-06-17.