Vulnerability in Microsoft Windows 11 23h2
CVE-2026-81963
Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (32.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
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.
Public proof-of-concept exploits
References
- Windows Update Stack Elevation of Privilege Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2026-81963?
- CVE-2026-81963 is a high-severity vulnerability in Microsoft Windows 11 23h2, classified under Improper Link Resolution Before File Access. CVSS score: 7.8/10. Published 2026-09-08.
- How severe is CVE-2026-81963?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2026-81963 known to be exploited?
- Yes. CVE-2026-81963 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-09-08), indicating it is being actively exploited. 1 public proof-of-concept repositories are indexed.