A heap-based buffer overflow, classified as CWE‑122, exists in the Windows Universal Disk Format File System Driver (UDFS). When an authorized user triggers the overflow, the attacker can overwrite heap memory and ultimately execute code with elevated privileges. This local privilege escalation can compromise OS integrity and any applications running under the hijacked account.

The flaw affects Microsoft Windows systems, including Windows 10 versions 1607, 1809, 21H2, and 22H2; Windows 11 versions 23H2, 24H2, 25H2, 26H2, 23H2, 26H1; and Windows Server releases 2012, 2012 R2, 2016, 2019, 2022, and 2025, on both x86 and x64 architectures and in Server Core installations.

The CVSS score of 7.8 classifies the vulnerability as high severity. The EPSS score is not available, and it is not listed in the CISA KEV catalog. The attack vector is local, requiring the attacker to already have authorized access to the target system. Once the heap overrun condition is achieved, the risk escalates sharply, enabling the attacker to gain elevated privileges and potentially execute arbitrary code.