---
id: CVE-2026-81963
title: >-
  Improper link resolution before file access ('link following') in Windows
  Update Stack allows an authorized attacker to elevate privileges locally.
summary: >-
  Improper link resolution before file access ('link following') in Windows
  Update Stack allows an authorized attacker to elevate privileges locally.
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-59
  - CWE-284
vendor: microsoft
product: windows_11_23h2
affected:
  - windows_11_23h2 < 10.0.22631.7582
  - windows_11_24h2 < 10.0.26100.9445
  - windows_11_25h2 < 10.0.26200.9445
  - windows_11_26h1 < 10.0.28000.2954
  - windows_server_2025 < 10.0.26100.33438
patched:
  - windows_11_23h2 10.0.22631.7582
  - windows_11_24h2 10.0.26100.9445
  - windows_11_25h2 10.0.26200.9445
  - windows_11_26h1 10.0.28000.2954
  - windows_server_2025 10.0.26100.33438
published: '2026-09-08'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T05:18:17.173'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81963'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963'
    label: secure@microsoft.com
  - url: >-
      https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - in-the-wild
  - exploit-available
  - kev
exploited: true
exploitAvailable: true
ssvc:
  exploitation: active
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-08T18:44:08.999075Z'
kev: true
kevDateAdded: '2026-09-08'
kevDueDate: '2026-09-22'
kevRansomware: false
zeroDay: true
ingestedAt: '2026-09-08T19:08:49.632Z'
epss: 0.00631
epssPercentile: 0.48518
---

## Overview

Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.

## Affected

- `windows_11_23h2 < 10.0.22631.7582`
- `windows_11_24h2 < 10.0.26100.9445`
- `windows_11_25h2 < 10.0.26200.9445`
- `windows_11_26h1 < 10.0.28000.2954`
- `windows_server_2025 < 10.0.26100.33438`

## Remediation

Upgrade past the affected range:

- `windows_11_23h2 10.0.22631.7582`
- `windows_11_24h2 10.0.26100.9445`
- `windows_11_25h2 10.0.26200.9445`
- `windows_11_26h1 10.0.28000.2954`
- `windows_server_2025 10.0.26100.33438`