Windows Update Stack Elevation of Privilege Vulnerability
Published Sep 8, 2026 ·Due Sep 22, 2026
7.8
HIGHCVSS 3.1
EPSS 0.39%
Description
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
Affected products
-
- Version 10.0.22631.0StatusaffectedConstraints<10.0.22631.7582
- Version
-
- Version 10.0.26100.0StatusaffectedConstraints<10.0.26100.9445
- Version
-
- Version 10.0.26200.0StatusaffectedConstraints<10.0.26200.9445
- Version
-
- Version 10.0.22631.0StatusaffectedConstraints<10.0.22631.7582
- Version
-
- Version 10.0.28000.0StatusaffectedConstraints<10.0.28000.2954
- Version
-
- Version 10.0.26100.0StatusaffectedConstraints<10.0.26100.33438
- Version
-
- Version 10.0.26100.0StatusaffectedConstraints<10.0.26100.33438
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Microsoft | Windows 11 Version 23H2 | n/a |
| ||||||
| Microsoft | Windows 11 Version 24H2 | n/a |
| ||||||
| Microsoft | Windows 11 Version 25H2 | n/a |
| ||||||
| Microsoft | Windows 11 version 23H2 | n/a |
| ||||||
| Microsoft | Windows 11 version 26H1 | n/a |
| ||||||
| Microsoft | Windows Server 2025 | n/a |
| ||||||
| Microsoft | Windows Server 2025 (Server Core installation) | n/a |
|
- < 10.0.22631.7582
- < 10.0.22631.7582
- < 10.0.26100.9445
- < 10.0.26100.9445
- < 10.0.26200.9445
- < 10.0.26200.9445
- < 10.0.28000.2954
- < 10.0.28000.2954
- < 10.0.26100.33438
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
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
1 other source (NVD) ▾
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
Date Added
Sep 8, 2026
Patch Due
Sep 22, 2026
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.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
ActiveAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Sep 7, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Sep–Oct 2026- EPSS v5
Percentile over time
- EPSS v5
Table of values (2 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.39% (0.00393) | 31.09th | v5 (v2026.06.15) |
| Sep 9, 2026 | 0.63% (0.00631) | 48.16th | v5 (v2026.06.15) |
References (2)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963 vendor-advisorypatchVendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963 government-resourceUS Government Resource
| Link | Providers | Tags |
|---|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963 | vendor-advisorypatchVendor Advisory | |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963 | government-resourceUS Government Resource |
Change history (0)
No recorded changes yet.