CVE-2026-81963
Status: AnalyzedHigh (7.8)⚠ Active exploitation
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Base score: 7.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.39%
- Percentile among all scored CVEs: 31
- Score date: 9/30/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
CISA KEV — actively exploited
- Added to catalog: 9/8/2026
- Remediation due date: 9/22/2026
- Known ransomware use: Unknown
Affected technologies (5)
CWEs
- CWE-59, CWE-284
References
Raw JSON (NVD)
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"tags": [
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{
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"lastModified": "2026-09-09T05:18:17.173",
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"cisaExploitAdd": "2026-09-08",
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"cisaRequiredAction": "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.",
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}