Microsoft Windows ulGetNearestIndexFromColorref Out-Of-Bounds Write Privilege Escalation Vulnerability

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 ulGetNearestIndexFromColorref function in win32k.sys. The issue results from the lack of proper validation of user-supplied data, which can result in a write outside the bounds of an allocated array. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of SYSTEM.