CVE-2026-88102
Windows Server 2019: Microsoft Failover Cluster Remote Code Execution Vulnerability
Microsoft Windows Server 2019Operating systems
CVSS
9.8CriticalExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.63%Chance of exploitation activity in the next 30 days, higher than 49% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 10.0.17763.9376Windows Server 2019CVE List
- 10.0.17763.9376Windows Server 2019 (Server Core installation)CVE List
- 10.0.20348.5761Windows Server 2022CVE List
- 10.0.26100.33650Windows Server 2025CVE List
- 10.0.26100.33650Windows Server 2025 (Server Core installation)CVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Vendor and government advisories 1
Vendors that say their products are affected, and agencies that issued alerts. Check each for the fixed release of the product you run.
Reports 1
1 outlet mention it. Reports are not confirmation; each links to its source.
Description
Use after free in Windows Failover Cluster allows an unauthorized attacker to execute code over a network.
Text from CVE List
Affected versions 5
- Windows Server 2019affected: 10.0.17763.0 before 10.0.17763.9376CVE List
- Windows Server 2019 (Server Core installation)affected: 10.0.17763.0 before 10.0.17763.9376CVE List
- Windows Server 2022affected: 10.0.20348.0 before 10.0.20348.5761CVE List
- Windows Server 2025affected: 10.0.26100.0 before 10.0.26100.33650CVE List
- Windows Server 2025 (Server Core installation)affected: 10.0.26100.0 before 10.0.26100.33650CVE List