CVE-2021-41465: CONCRETE5-Legacy Project CONCRETE5-Legacy

Medium severity, CVSS 6.1. EPSS: 0.8% chance of exploitation in the next 30 days.

Cross-site scripting (XSS) vulnerability in concrete/elements/collection_theme.php in concrete5-legacy 5.6.4.0 and below allows remote attackers to inject arbitrary web script or HTML via the rel parameter.

Affected products

• CONCRETE5-Legacy Project CONCRETE5-Legacy: up to and including 5.6.4.0

Published 2021-10-01. Last modified 2026-06-17.