The vulnerability is an out‑of‑bounds read in the Windows Network Policy Server (NPS) service. An attacker who can target the NPS service can trigger a read beyond buffer limits, leading the system to crash or become unresponsive for NPS‑dependent traffic. The fault does not enable code execution or privilege escalation, but it disables authentication and authorization services for clients that rely on NPS, resulting in a denial‑of‑service.

Microsoft Windows 10 versions 1607, 1809, 21H2, and 22H2; Windows 11 versions 23H2, 24H2, 25H2, 26H2, and 26H1; Windows Server 2012, Server Core installations, 2012 R2, Server Core installations, 2016, 2019, 2022, and 2025, including Server Core variants.

The flaw carries a CVSS score of 7.5, indicating moderate‑to‑high severity. The EPSS score of 1% indicates a low but nonzero probability that the vulnerability is being actively exploited, and the vulnerability is not listed in the CISA KEV catalog. Attackers likely require network access to the NPS service and can exploit the flaw remotely by sending crafted requests that trigger the out‑of‑bounds read. Because the impact is a denial of service, organizations should evaluate whether the NPS role is essential and apply the Microsoft patch as soon as possible.