This vulnerability allows local attackers to escalate privileges on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
The specific flaw exists within the Windows Image Acquisition service. By creating a junction, an attacker can abuse the service to overwrite the contents of a chosen file. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of SYSTEM.
Microsoft has issued an update to correct this vulnerability. More details can be found at: