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Fencer Intel
high 7.8

CVE-2026-81963 kev in the critical feed json

Windows Update Stack Elevation of Privilege Vulnerability

published 2mo ago modified yesterday also EUVD-2026-73889

cvss
7.8
version 3.1, CNA
cisa kev
Exploited
added 2026-09-08
epss
7.1%
EPSS 7.1% chance of exploitation in 30 days, percentile 94%
public exploits
0
none known

Summary

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

Patch / fix

cisa required action 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.

  • Microsoft Windows 11 version 23H2 10.0.22631.7582
  • Microsoft Windows 11 Version 24H2 10.0.26100.9445
  • Microsoft Windows 11 Version 25H2 10.0.26200.9445
  • Microsoft Windows 11 version 26H1 10.0.28000.2954
  • Microsoft Windows Server 2025 10.0.26100.33438
  • Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.33438

Is CVE-2026-81963 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Timeline

  1. CISA SSVC: exploitation active
  2. Added to CISA KEV
  3. Published
  4. CISA patch deadline

Known exploited

Added
2mo ago
Patch by
2026-09-22 (last mo.)
Ransomware
Not known
Required action
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.
Vendor, product
Microsoft, Windows
CISA name
Microsoft Windows Link Following Vulnerability

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
no
Technical impact
total
Assessed
2mo ago

Exploit prediction

7.12% chance of exploitation in the next 30 days, higher than 94% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Microsoft Windows 11 version 23H2
  • Microsoft Windows 11 Version 24H2
  • Microsoft Windows 11 Version 25H2
  • Microsoft Windows 11 version 26H1
  • Microsoft Windows Server 2025
  • Microsoft Windows Server 2025 (Server Core installation)

Classification

Weakness
  • CWE-59 Improper Link Resolution Before File Access
  • CWE-284 Improper Access Control

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.