CVE-2026-81963

Analyzed
Published: 08 Sept 2026, 17:19
Last modified:09 Sept 2026, 04:25

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
v3.1 (cve.org)
EPSS Score
No data
KEV
Listed
CISA
1 listing
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

08 Sept 2026, 17:19
Published
Vulnerability first disclosed
08 Sept 2026, 00:00
Added to CISA KEV
Microsoft Windows Link Following Vulnerability
09 Sept 2026, 04:25
Last Modified
Vulnerability information updated
22 Sept 2026, 00:00
CISA Remediation Due
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Description

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

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Techniques & Countermeasures

  • CWE-59•Improper Link Resolution Before File Access ('Link Following')

    The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

  • CWE-284•Improper Access Control

    The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Affected Systems

  • microsoft•windows_11_23h2

    < 10.0.22631.7582

  • microsoft•windows_11_24h2

    < 10.0.26100.9445

  • microsoft•windows_11_25h2

    < 10.0.26200.9445

  • microsoft•windows_11_26h1

    < 10.0.28000.2954

  • microsoft•windows 11 version 23h2

    ≥ 10.0.22631.0, < 10.0.22631.7582

  • microsoft•windows 11 version 24h2

    ≥ 10.0.26100.0, < 10.0.26100.9445

  • microsoft•windows 11 version 25h2

    ≥ 10.0.26200.0, < 10.0.26200.9445

  • microsoft•windows 11 version 26h1

    ≥ 10.0.28000.0, < 10.0.28000.2954

  • microsoft•windows server 2025

    < 10.0.26100.33438 | ≥ 10.0.26100.0, < 10.0.26100.33438

  • microsoft•windows server 2025 (server core installation)

    ≥ 10.0.26100.0, < 10.0.26100.33438

References (2)