High MSRC-CVE-2026-88099 1 CVE

Windows Failover Cluster Denial of Service Vulnerability

Published Oct 13, 2026 · Updated Oct 13, 2026

Vendor: Microsoft

Summary

Impact: Denial of Service. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

Security updates
10.0.17763.9376 — https://support.microsoft.com/help/5126651
10.0.20348.5761 — https://support.microsoft.com/help/5126655
10.0.26100.33650 — https://support.microsoft.com/help/5126646

Vulnerabilities 1

Medium 5.9

CVE-2026-88099

Windows Failover Cluster Denial of Service Vulnerability

Uncaught exception in Windows Failover Cluster allows an unauthorized attacker to deny service over a network.

Microsoft Windows Server 2019 Windows Server 2019 (Server Core installation) Windows Server 2022 Windows

Oct 13, 2026

Revision history

2026-10-13 #1
Information published.

References

CVE-2026-88099 Windows Failover Cluster Denial of Service Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88099
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss