What is CVE-2026-72989?

CVE-2026-72989 is a high-severity vulnerability in Microsoft Windows 10 Version 1809, classified under Use of Uninitialized Resource. CVSS score: 7.5/10. Published 2026-09-08.

How severe is CVE-2026-72989?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Microsoft Windows 10 Version 1809

CVE-2026-72989

Use of uninitialized resource in Windows Failover Cluster allows an unauthorized attacker to disclose information over a network.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Microsoft Windows 10 Version 1809
Microsoft Windows Server 2019
Microsoft Windows Server 2019 (Server Core Installation)
Microsoft Windows Server 2022
Microsoft Windows Server 2025
Microsoft Windows Server 2025 (Server Core Installation)

Weakness classification (CWE)

CWE-908 — Use of Uninitialized Resource

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-72989?: CVE-2026-72989 is a high-severity vulnerability in Microsoft Windows 10 Version 1809, classified under Use of Uninitialized Resource. CVSS score: 7.5/10. Published 2026-09-08.
How severe is CVE-2026-72989?: High severity. CVSS v3 base score is 7.5 out of 10.