Technical Information

Brief overview of the risk:
This security update resolves a privately reported vulnerability in Active Directory, Active Directory Application Mode (ADAM), and Active Directory Lightweight Directory Service (AD LDS). The vulnerability could allow elevation of privilege if Active Directory is configured to use LDAP over SSL (LDAPS) and an attacker acquires a revoked certificate that is associated with a valid domain account and then uses that revoked certificate to authenticate to the Active Directory domain. By default, Active Directory is not configured to use LDAP over SSL.
Detailed Information on the risk:

An elevation of privilege vulnerability exists in Active Directory when configured to use LDAP over SSL (LDAPS). An attacker could exploit this vulnerability by using a previously revoked certificate to authenticate to the Active Directory domain and gain access to network resources or run code under the privileges of a specific authorized user with which the certificate is associated.

Further information on this exploit is available at : MS11-086