Technical Information

Brief overview of the risk:
This security update resolves vulnerabilities in Microsoft Windows. The more severe of these vulnerabilities could allow elevation of privilege if an attacker logs on locally and runs arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

Detailed Information on the risk:

An elevation of privilege vulnerability exists when the Win32k.sys kernel-mode driver improperly handles objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take complete control over an affected system.

Further information on this exploit is available at : MS15-051

Windows Server 2003 Service Pack 2 
Windows Server 2003 x64 Edition Service Pack 2 
Windows Server 2003 with SP2 for Itanium-based Systems 
Windows Vista Service Pack 2 
Windows Vista x64 Edition Service Pack 2 
Windows Server 2008 for 32-bit Systems Service Pack 2 
Windows Server 2008 for x64-based Systems Service Pack 2 
Windows Server 2008 for Itanium-based Systems Service Pack 2 
Windows 7 for 32-bit Systems Service Pack 1 
Windows 7 for x64-based Systems Service Pack 1 
Windows Server 2008 R2 for x64-based Systems Service Pack 1 
Windows Server 2008 R2 for Itanium-based Systems Service Pack 1 
Windows 8 for 32-bit Systems 
Windows 8 for x64-based Systems 
Windows 8.1 for 32-bit Systems 
Windows 8.1 for x64-based Systems 
Windows Server 2012 and Windows Server 2012 R2
Windows Server 2012 
Windows Server 2012 R2 
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) 
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 
Windows Server 2012 (Server Core installation) 
Windows Server 2012 R2 (Server Core installation)