VDB
CVE-2026-81963
CVE-2026-81963
PUBLISHED
CVSS 7.8 HIGH
Windows Update Stack Elevation of Privilege Vulnerability
Reported by microsoft · Published September 8, 2026
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| Windows 11 Version 23H2 | Microsoft | 10.0.22631.7582 |
| windows_server_2025 | microsoft | 10.0.26100.33438 |
Risk scores
CVSS 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
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 |
| microsoft | windows_11_26H1 | 10.0.28000.0 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 |
| microsoft | windows_11_24H2 | 10.0.26100.0 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 |
| microsoft | windows_11_25H2 | 10.0.26200.0 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 |
| microsoft | windows_server_2025 | 10.0.26100.0 |
| microsoft | windows_11_23H2 | 10.0.22631.0 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 |
Timeline
- Sep 8, 2026 CISA KEV Added
- Sep 8, 2026 VulnCheck KEV Exploitation
- Sep 8, 2026 Coalition ESS Score
- Sep 8, 2026 CVE Published
- Sep 9, 2026 EPSS Score (25 in total, the first dated here)
- Nov 10, 2026 VulnCheck XDB Entry
- Nov 10, 2026 CVE Updated
- Nov 11, 2026 Security Advisory
Query this with the API
The same record, from the CLI:
vulnetix vdb vuln CVE-2026-81963
vulnetix vdb fixes CVE-2026-81963Or with curl, using the org id and key from your account page:
curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
"https://api.vdb.vulnetix.com/v2/vuln/CVE-2026-81963/fixes/registry"The Community plan is free and allows 50 queries a day. Get a free API key · API quickstart