CVE intelligenceCISA KEV

CVE-2026-81963

Microsoft Windows Link Following Vulnerability

Published Sep 8, 2026Sources checked Oct 28, 2026

7.8HIGHCVSS out of 10

What this means

Actively exploited

CISA lists CVE-2026-81963 in its Known Exploited Vulnerabilities catalog, which means exploitation has been observed. The entry applies to Microsoft Windows.

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.

Public exploit: Not collected.

Microsoft Security Response Center: Exploitation reported by Microsoft Security Response Center (2026-10-07)
Microsoft exploitation status: Exploited:Yes

What to do next

Remediation and response

Review the linked vendor advisory and apply the mitigation or fixed release for your affected product.

Microsoft Security Response Center guidance

Vendor revision: Oct 7, 2026

Vendor remediation details

Install KB5122871. Install KB5124008. Install KB5122880. Install KB5124012.

Vendor-listed releases

10.0.26100.33438
10.0.26200.9445
10.0.22631.7582
10.0.26100.9445
10.0.28000.2954

CISA KEVListedObserved exploitation

EPSS0.4%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors1Source-linked actor relationships

Overview

What is CVE-2026-81963?

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

Source: NVD

Reported activity: Microsoft exploitation status: Exploited:Yes
Microsoft Security Response Center · Published Oct 7, 2026

CISA says: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 catalog due date Sep 22, 2026