A null pointer dereference occurs within the Windows VMSwitch component, making an authorized local attacker able to trigger a denial of service. The flaw causes the VMSwitch service to crash, disrupting virtual network connectivity for any virtual machines that rely on it. While it does not directly threaten confidentiality or integrity, the resulting loss of service can severely hamper the availability of virtualized workloads.

The vulnerability affects multiple Microsoft Windows releases. Client systems such as Windows 10 version 1809, 21H2, and 22H2 and Windows 11 versions 23H2, 24H2, 25H2, 26H2 (including ARM64 variants) are impacted. Server installations, including Windows Server 2019 (standard and Server Core), Windows Server 2022, and Windows Server 2025 (standard and Server Core), may also be affected.

The CVSS score of 5.6 indicates moderate severity. EPSS data is not available, limiting assessment of real‑world exploitation likelihood. The vulnerability is not listed in CISA’s KEV catalog. Attackers must first acquire local elevated privileges to exploit the null pointer dereference, making the vector likely to be an authorized local attack. Given VMSwitch’s importance to virtual network infrastructure, the availability impact can be significant in environments that rely heavily on Hyper‑V networking.