This vulnerability allows local attackers to escalate privileges on vulnerable 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 handling of bitmap objects. By performing a certain sequence of calls to win32k.sys, an attacker can cause the kernel to make use of a null pointer. An attacker can leverage this vulnerability to escalate privilege to SYSTEM.