CVE-2026-81963

HIGH CVSS 3.1: 7.8 EPSS 0.63% ACTIVE EXPLOIT
Updated Sep 09, 2026
Microsoft

CISA Known Exploited Vulnerability (KEV)

This vulnerability is actively exploited in the wild. Immediate patching is strongly recommended.

Due Date: Sep 22, 2026

Parameter Value
CVSS 7.8 (HIGH)
Affected Versions 10.0.22631.0 — 10.0.28000.2954
Fixed In 10.0.22631.7582
Type CWE-284 (Improper Access Control), CWE-59 (Improper Link Resolution)
Vendor Microsoft
Public PoC Yes

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

Attack Parameters

Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v3.1

Vulnerable Products 14

Configuration From (including) Up to (excluding)
Microsoft Windows_11_23h2
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*
10.0.22631.7582
Microsoft Windows_11_23h2
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*
10.0.22631.7582
Microsoft Windows_11_24h2
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*
10.0.26100.9445
Microsoft Windows_11_24h2
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*
10.0.26100.9445
Microsoft Windows_11_25h2
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*
10.0.26200.9445
Microsoft Windows_11_25h2
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*
10.0.26200.9445
Microsoft Windows_11_26h1
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*
10.0.28000.2954
Microsoft Windows_11_26h1
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*
10.0.28000.2954
Microsoft Windows_Server_2025
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*
10.0.26100.33438
Microsoft Windows_11_25h2
cpe:2.3:o:microsoft:windows_11_25H2:*:*:*:*:*:*:arm64:*
10.0.26200.0 10.0.26200.9445
Microsoft Windows_11_23h2
cpe:2.3:o:microsoft:windows_11_23H2:*:*:*:*:*:*:arm64:*
10.0.22631.0 10.0.22631.7582
Microsoft Windows_11_23h2
cpe:2.3:o:microsoft:windows_11_23H2:*:*:*:*:*:*:x64:*
10.0.22631.0 10.0.22631.7582
Microsoft Windows_11_24h2
cpe:2.3:o:microsoft:windows_11_24H2:*:*:*:*:*:*:arm64:*
10.0.26100.0 10.0.26100.9445
Microsoft Windows_11_26h1
cpe:2.3:o:microsoft:windows_11_26H1:*:*:*:*:*:*:x64:*
10.0.28000.0 10.0.28000.2954