Microsoft Windows Security Update for Digital Certificates Spoofing Vulnerability
IntelliShield: Security Activity Bulletin
2012 June 04 16:16 GMT
2012 June 07 18:29 GMT
Additional technical information that describes the Microsoft Windows security update for digital certificates spoofing vulnerability is available.
Microsoft Windows contains a vulnerability that could allow an unauthenticated, remote attacker to conduct spoofing, phishing, or man-in-the-middle (MITM) attacks on a targeted system.
This update fixes a spoofing vulnerability in the affected software that results from the unauthorized use of digital certificates from a Microsoft Certificate Authority associated with Terminal Server licensing. The update revokes the trust of two Microsoft Enforced Licensing Intermediate PCA and one Microsoft Enforced Licensing Registration Authority CA certificates.
An unauthenticated, remote attacker could exploit the vulnerability by creating unauthorized digital certificates that could be use to trick a user into trusting the certificates. If successful, an attacker could have the ability to conduct spoofing, MITM, or phishing attacks.
A successful exploit on systems that use Windows Vista or later versions of Windows would require an attacker to have access to the Terminal Server Licensing Service certificates (which are now invalid) and the ability to perform MD5 hash collision attacks. Systems prior to Windows Vista can be exploited without an MD5 hash collision.
An attack vector to exploit this vulnerability would be the use of the system's automatic update program, which an attacker could use to install unauthorized digital certificates on a targeted system. Microsoft has acknowledged this attack vector, and additional steps are being taken to protect the Windows Update infrastructure from use in further attacks.
Administrators are advised to apply the appropriate updates.
Microsoft has released a security advisory at the following link: 2718704
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Windows Update website. Microsoft Windows Server Update Services (SUBS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Cisco Systems Cisco Intrusion Prevention System (IPS) 6.0
Version 1, June 4, 2012, 11:16 AM: Microsoft Windows contains a vulnerability that could allow an unauthenticated, remote attacker to conduct spoofing, phishing, or man-in-the-middle attacks. Updates are available.
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