CVE-2026-21251 | Microsoft Windows Cluster Client Failover use after free
A vulnerability categorized as critical has been discovered in Microsoft Windows Server 2016/Server 2019/Server 2022/Server 2022 23H2/Server 2025. This affects an unknown function of the component Cluster Client Failover. The manipulation results in use after free.
This vulnerability is identified as CVE-2026-21251. The attack is only possible with local access. There is not any exploit available.
It is advisable to implement a patch to correct this issue.