Executive brief
A security vulnerability has been identified in the Windows Win32K component, which manages graphics and windowing for the operating system. An attacker who already has basic access to a system could exploit this flaw to gain full administrative control. This could lead to unauthorized access to sensitive data, the ability to install malicious software, or the disruption of critical business operations.
Technical details
A use-after-free vulnerability (CWE-416) exists in the Windows Win32K kernel-mode driver, specifically within the ICOMP component. The flaw is triggered when the system improperly handles objects in memory, allowing an attacker to reuse a memory pointer after it has been freed. To exploit this, an attacker must first gain local access to the target system with low-level user privileges. Successful exploitation allows the attacker to execute arbitrary code in kernel mode, leading to a full local privilege escalation (LPE) to SYSTEM. Microsoft has released security updates to address this issue across affected versions of Windows 11 and Windows Server 2022.
Affected products
- Microsoft Windows 11 Version 23H2 10.0.22631.0 up to 10.0.22631.6491
- Microsoft Windows Server 2022 10.0.20348.0 up to 10.0.20348.4648
- Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.0 up to 10.0.25398.2092
Timeline
- 2026-01-13: disclosed: Initial publication of the vulnerability advisory.
- 2026-01-13: patched: Microsoft released security updates to address the flaw.