CVE-2006-5504: Simple Machines Forum

Medium severity, CVSS 4.3. EPSS: 1.2% chance of exploitation in the next 30 days.

Cross-site scripting (XSS) vulnerability in index.php in Simple Machines Forum (SMF) allows remote attackers to inject arbitrary web script or HTML via a base64 encoded params value in the action parameter.

Affected products

• Simple Machines Simple Machines Forum: version 1.0.5 only; version 1.0.6 only; version 1.0.7 only; version 1.1_rc1 only; version 1.1_rc2 only; version 1.1_rc3 only

Published 2006-10-25. Last modified 2026-06-16.