---
id: CVE-2026-72989
title: >-
  Use of uninitialized resource in Windows Failover Cluster allows an
  unauthorized attacker to disclose information over a network.
summary: >-
  Use of uninitialized resource in Windows Failover Cluster allows an
  unauthorized attacker to disclose information over a network.
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-908
vendor: microsoft
product: windows_10_1809
affected:
  - windows_10_1809 < 10.0.17763.9245
  - windows_server_2019 < 10.0.17763.9245
  - windows_server_2022 < 10.0.20348.5622
  - windows_server_2025 < 10.0.26100.33438
patched:
  - windows_10_1809 10.0.17763.9245
  - windows_server_2019 10.0.17763.9245
  - windows_server_2022 10.0.20348.5622
  - windows_server_2025 10.0.26100.33438
published: '2026-09-08'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T15:33:38.630'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-72989'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-72989'
    label: secure@microsoft.com
tags:
  - nvd
  - cve.org
epss: 0.01027
epssPercentile: 0.62108
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-08T19:43:55.521386Z'
ingestedAt: '2026-09-08T19:08:49.626Z'
---

## Overview

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

## Affected

- `windows_10_1809 < 10.0.17763.9245`
- `windows_server_2019 < 10.0.17763.9245`
- `windows_server_2022 < 10.0.20348.5622`
- `windows_server_2025 < 10.0.26100.33438`

## Remediation

Upgrade past the affected range:

- `windows_10_1809 10.0.17763.9245`
- `windows_server_2019 10.0.17763.9245`
- `windows_server_2022 10.0.20348.5622`
- `windows_server_2025 10.0.26100.33438`