Exploitation evidence
Known exploited · CISA KEV listed
Added 2026-09-08. Ransomware campaign use: Unknown.
CISA 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 due date: 2026-09-22. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Microsoft / Windows 11 version 23H2
Default status: Not specified
- affected: 10.0.22631.0 to < 10.0.22631.7582 (custom)
Microsoft / Windows 11 Version 23H2
Default status: Not specified
- affected: 10.0.22631.0 to < 10.0.22631.7582 (custom)
Microsoft / Windows 11 Version 24H2
Default status: Not specified
- affected: 10.0.26100.0 to < 10.0.26100.9445 (custom)
Microsoft / Windows 11 Version 25H2
Default status: Not specified
- affected: 10.0.26200.0 to < 10.0.26200.9445 (custom)
Microsoft / Windows 11 version 26H1
Default status: Not specified
- affected: 10.0.28000.0 to < 10.0.28000.2954 (custom)
Microsoft / Windows Server 2025
Default status: Not specified
- affected: 10.0.26100.0 to < 10.0.26100.33438 (custom)
Microsoft / Windows Server 2025 (Server Core installation)
Default status: Not specified
- affected: 10.0.26100.0 to < 10.0.26100.33438 (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.07115,
"percentile": 0.94334
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.00393,
"percentile": 0.33853
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.00393,
"percentile": 0.33798
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.00393,
"percentile": 0.33781
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.00393,
"percentile": 0.33761
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.00393,
"percentile": 0.33715
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.00393,
"percentile": 0.33704
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.00393,
"percentile": 0.33695
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.00393,
"percentile": 0.33579
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.00393,
"percentile": 0.3353
}03 Nov 2026, 02:22 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
"containers": {
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"metrics": [
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"version": "2.0.3"
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"value": "Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally."
}
],
"metrics": [
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"datePublished": "2026-09-08T17:19:13.121Z",
"dateReserved": "2026-08-27T20:58:07.631Z",
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}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2026-81963",
"cwes": [
"CWE-59",
"CWE-284"
],
"dateAdded": "2026-09-08",
"dueDate": "2026-09-22",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"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",
"product": "Windows",
"requiredAction": "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.",
"shortDescription": "Microsoft Windows Update Stack contains a link following vulnerability that allows a local attacker to escalate privileges locally up to SYSTEM.",
"vendorProject": "Microsoft",
"vulnerabilityName": "Microsoft Windows Link Following Vulnerability"
}