This vulnerability is a heap-based buffer overflow in the Windows Kernel that permits an attacker who already has local access to gain higher privileges. The flaw resides in untrusted input handling within kernel memory, leading to an overrun that can overwrite control data and elevate the user’s permissions. As a result, an attacker could execute code with SYSTEM rights, compromising the entire system’s confidentiality, integrity, and availability.

Affected versions include Microsoft Windows 10 versions 1809, 21H2, and 22H2; Windows 11 versions 23H2, 24H2, 25H2, 26H2, and 26H1; and Windows Server releases 2019, 2022, and 2025, both in full and Server Core installations. The issue is present across x86, x64, and ARM64 architectures as listed in the affected CPEs.

The evaluated CVSS score of 7.8 indicates a high severity vulnerability with the potential to impact confidentiality and integrity. EPSS is not available, but the lack of a KEV listing suggests no known active exploitation at the time of analysis. The flaw requires local user or service privilege to manipulate kernel memory, but does not allow remote exploitation. The risk remains significant for any system running the affected versions without the corresponding patch.