Microsoft Windows Link Following Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
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 notes
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-81963 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-81963
Description
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
Severity
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:CExploitation Context
as of October 14, 2026- CISA added CVE-2026-81963 to the KEV catalog on the day its CVE record was published. The median for entries added in 2026 so far is 15 days.
- It is one of 391 Microsoft entries in the CISA KEV catalog, and one of 40 added in 2026.
Affected Products
| Vendor | Product | Affected versions |
|---|---|---|
| Microsoft | Microsoft Windows 11 version 23H2 | 10.0.22631.0 to <10.0.22631.7582 |
| Microsoft | Microsoft Windows 11 Version 23H2 | 10.0.22631.0 to <10.0.22631.7582 |
| Microsoft | Microsoft Windows 11 Version 24H2 | 10.0.26100.0 to <10.0.26100.9445 |
| Microsoft | Microsoft Windows 11 Version 25H2 | 10.0.26200.0 to <10.0.26200.9445 |
| Microsoft | Microsoft Windows 11 version 26H1 | 10.0.28000.0 to <10.0.28000.2954 |
| Microsoft | Microsoft Windows Server 2025 | 10.0.26100.0 to <10.0.26100.33438 |
| Microsoft | Microsoft Windows Server 2025 (Server Core installation) | 10.0.26100.0 to <10.0.26100.33438 |
References
1 LinksRecord Details
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Related
Tool categories
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