CVE-2026-72989: Windows Failover Cluster Information Disclosure Vulnerability

Overview

Severity

High (CVSS 7.5)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Category

Information Disclosure

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Sep

Released

2026-09-08

Description

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

FAQ

What type of information could be disclosed by this vulnerability? The type of information that could be disclosed if an attacker successfully exploited this vulnerability is uninitialized stack memory.

Affected Products (8)

Windows

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows Server 2025 (Server Core installation)
• Windows Server 2025

Security Updates (3)

• 5122876
• 5122882
• 5122871

Acknowledgments

41ae55e9310ff27fa6f26af4727e5590

Revision History

• 2026-09-08: Information published.