CVE-2011-5061: Whmcs Whmcompletesolution

High severity, CVSS 7.5. EPSS: 2.2% chance of exploitation in the next 30 days.

functions.php in WHMCompleteSolution (WHMCS) 4.0.x through 5.0.x allows remote attackers to trigger arbitrary code execution in the Smarty templating system by submitting a crafted ticket, related to improper handling of characters in the subject field.

Affected products

• Whmcs Whmcompletesolution: version 4.0.0 only; version 4.0.1 only; version 4.0.2 only; version 4.1.0 only; version 4.1.1 only; version 4.1.2 only; …

Published 2012-01-14. Last modified 2026-06-16.