Cross-site scripting (XSS) vulnerability in +webvpn+/index.html in WebVPN on the Cisco Adaptive Security Appliances (ASA) 5520 with software 7.2(4)30 and earlier 7.2 versions including 7.2(2)22, and 8.0(4)28 and earlier 8.0 versions, when clientless mode is enabled, allows remote attackers to inject arbitrary web script or HTML via the Host HTTP header.