Microsoft Active Directory Federation Services Information Disclosure Vulnerability

An information disclosure vulnerability exists when Active Directory Federation Services (AD FS) fails to properly log off a user. The vulnerability could allow unintentional information disclosure. An attacker who successfully exploited this vulnerability could gain access to a user's information by reopening an application from which the user has logged off. Since the logoff actually fails an attacker is not prompted to enter a username or password. An attacker could then use this vulnerability to discover information to which an AD FS user has access.