CVE-2026-83991: CWE-306: Missing Authentication for Critical Function in Microsoft Windows 10 Version 1809
Missing authentication for critical function in Windows Cloud Files Mini Filter Driver allows an authorized attacker to perform tampering locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-83991) involves missing authentication controls in the Windows Cloud Files Mini Filter Driver on Windows 10 Version 1809 (build 10.0.17763.0). The lack of authentication for a critical function enables an attacker with local authorized access to perform tampering actions. The CVSS 3.1 base score is 5.5 (medium severity), reflecting local attack vector, low complexity, required privileges, no user interaction, and impact limited to integrity. Microsoft has published an official fix for this vulnerability.
Potential Impact
An authorized local attacker can exploit this vulnerability to tamper with system components related to the Cloud Files Mini Filter Driver, potentially compromising system integrity. There is no confidentiality or availability impact reported. No known exploits are currently active in the wild.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83991 to remediate this vulnerability.
CVE-2026-83991: CWE-306: Missing Authentication for Critical Function in Microsoft Windows 10 Version 1809
Description
Missing authentication for critical function in Windows Cloud Files Mini Filter Driver allows an authorized attacker to perform tampering locally.
CVSS v3.1
Score 5.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-83991) involves missing authentication controls in the Windows Cloud Files Mini Filter Driver on Windows 10 Version 1809 (build 10.0.17763.0). The lack of authentication for a critical function enables an attacker with local authorized access to perform tampering actions. The CVSS 3.1 base score is 5.5 (medium severity), reflecting local attack vector, low complexity, required privileges, no user interaction, and impact limited to integrity. Microsoft has published an official fix for this vulnerability.
Potential Impact
An authorized local attacker can exploit this vulnerability to tamper with system components related to the Cloud Files Mini Filter Driver, potentially compromising system integrity. There is no confidentiality or availability impact reported. No known exploits are currently active in the wild.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83991 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-01T01:02:23.997Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83991","vendor":"Microsoft"}]
Threat ID: 6aa0457bacd9273b49fbdf65
Added to database: 09/08/2026, 17:27:23 UTC
Last enriched: 09/08/2026, 17:38:18 UTC
Last updated: 09/09/2026, 01:10:43 UTC
Views: 7
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