CVE-2026-88102: Microsoft Failover Cluster Remote Code Execution Vulnerability
Microsoft Failover Cluster Remote Code Execution Vulnerability
Other sources
Use after free in Windows Failover Cluster allows an unauthorized attacker to execute code over a network.
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9376Patch KB5126651
Event History
Frequently Asked Questions
Which systems should be prioritized for investigation?
Windows Server 2019, Windows Server 2022, and Windows Server 2025 systems running Microsoft Failover Cluster should be prioritized. The vulnerability is remotely exploitable and does not require authentication or user interaction.
What level of access does an attacker need to exploit this issue?
An attacker can exploit the vulnerability over the network without prior privileges or user interaction. Successful exploitation can result in code execution.
What is the likely impact of successful exploitation?
The published severity metrics indicate high impact to confidentiality, integrity, and availability. This means a successful attack could expose data, alter systems or data, and disrupt services.