The vulnerability is a heap-based buffer overflow in the Windows kernel that allows an authorised local user to gain elevated privileges. It is a classic out‑of‑bounds write (CWE‑122) that can corrupt critical kernel structures, potentially enabling the attacker to execute arbitrary code with SYSTEM rights.

Affected systems include Microsoft Windows 10 (versions 1607, 1809, 21H2, 22H2) and Windows 11 (versions 23H2, 24H2, 25H2, 26H2 and the 26H2 build for arm64) as well as all Windows Server releases from 2012 (including core installations) through 2025.

The vulnerability has a CVSS score of 7.8, indicating a high severity for local privilege escalation. No EPSS score is available, and it is not currently listed in the CISA KEV catalog. Because the affected users must already be authorized on the host, the attack vector is likely local. No publicly disclosed exploitation code has been reported, so the risk is moderate to high when a valid local account exists.