A heap‑based buffer overflow occurs in the Windows Partition Management Driver, allowing an attacker who already has local user or service access to gain elevated privileges on the affected system. The vulnerability could be exploited to elevate a user’s privileges to that of an administrator, thereby enabling arbitrary code execution, data modification, or denial of service at the system level.

The flaw affects multiple Windows operating systems: Windows 10 versions 21H2 and 22H2; Windows 11 versions 23H2, 24H2, 25H2, and 26H1; Windows Server 2022; and Windows Server 2025, including both full and Server Core installations. The affected architectures include x86, x64, and arm64 devices.

The CVSS score of 7.8 indicates high severity, and although the EPSS score is currently unavailable, the vulnerability is not listed in the CISA KEV catalog. It is exploitable from a local machine by an authenticated user; the attack vector requires local execution of crafted data to trigger the buffer overflow. Once triggered, the attacker can obtain administrative rights, bypassing the system’s security boundaries.