Cross-site scripting (XSS) vulnerability in cookieauth.dll in the HTML forms authentication component in Microsoft Forefront Threat Management Gateway Medium Business Edition (TMG MBE); and Internet Security and Acceleration (ISA) Server 2006 2006 Supportability Update and 2006 SP1; allows remote attackers to inject arbitrary web script or HTML via \authentication input\ to this component aka \Cross-Site Scripting Vulnerability.\