CVE-2026-20920: Win32k Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 7.8)

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Unlikely

Patch Tuesday

2026-Jan

Released

2026-01-13

EPSS Score

0.03% (percentile: 10.2%)

Description

Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.

FAQ

What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Affected Products (5)

Windows

• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows 11 Version 23H2 for ARM64-based Systems
• Windows 11 Version 23H2 for x64-based Systems
• Windows Server 2022, 23H2 Edition (Server Core installation)

Security Updates (3)

• 5073457
• 5073455
• 5073450

Acknowledgments

Varun Goel

Revision History

• 2026-01-13: Information published.