The vulnerability was used by APT28 team along with another zero-day CVE-2017-0262.
Vulnerable component: Windows
CVSSv3 score: CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE-ID: CWE-20 - Improper Input Validation
The vulnerability allows a local user to elevate privileges on the system.
The vulnerability exists due to boundary error in Win32k.sys driver. A local user can escalate privileges on the system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Note: this vulnerability is being actively exploited.