Vulnerability details
CVE-2026-81963
Actively exploited
Microsoft Windows 11Microsoft Windows Server
Windows Update Stack Elevation of Privilege Vulnerability
CVSS 3.1
7.8High
Official description
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.8High | 3.1 | CVEProject cvelistV5 (CNA) (microsoft) | 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 | Source |
|---|---|---|---|
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 ≤ v < 10.0.26100.9445 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 ≤ v < 10.0.26200.9445 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 ≤ v < 10.0.22631.7582 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 ≤ v < 10.0.22631.7582 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 ≤ v < 10.0.28000.2954 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2025 | 10.0.26100.0 ≤ v < 10.0.26100.33438 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 ≤ v < 10.0.26100.33438 | CVEProject cvelistV5 (CNA) |
References and advisories
2- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963 vendor-advisorypatch
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963 government-resource
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Details
- Published
- 2026-09-08
- Last updated
- 2026-11-11
- State
- Published
- Assigner (CNA)
- microsoft
- Kolun priority
- 70 · High
CISA KEV catalog
- Date added
- 2026-09-08
- Due date
- 2026-09-22
- Used in ransomware
- Unknown
Exploit prediction (EPSS)
0.39%
Probability of exploitation in 30 days
33.7%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Active
- Technical impact
- Total
Weaknesses (CWE)
- CWE-59Improper Link Resolution Before File Access ('Link Following')
- CWE-284Improper Access Control