CVE-2025-21340: CWE-284: Improper Access Control in Microsoft Windows 10 Version 1809
Windows Virtualization-Based Security (VBS) Security Feature Bypass Vulnerability
AI Analysis
Technical Summary
CVE-2025-21340 is an improper access control vulnerability (CWE-284) affecting Windows Virtualization-Based Security (VBS) in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw allows a local attacker with low privileges to bypass security controls implemented by VBS, potentially leading to unauthorized access to sensitive information. The vulnerability has a CVSS 3.1 base score of 5.5, indicating medium severity, with attack vector local, low attack complexity, and no user interaction required. Microsoft has released an official fix to address this issue.
Potential Impact
An attacker with limited privileges on a vulnerable Windows 10 Version 1809 system could bypass VBS security features, potentially gaining unauthorized access to sensitive data or resources protected by virtualization-based security. The vulnerability does not impact system integrity or availability directly and requires local access.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. It is recommended to apply the security update provided by Microsoft as detailed in their advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21340 to remediate this issue.
CVE-2025-21340: CWE-284: Improper Access Control in Microsoft Windows 10 Version 1809
Description
Windows Virtualization-Based Security (VBS) Security Feature Bypass Vulnerability
CVSS v3.1
Score 5.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-21340 is an improper access control vulnerability (CWE-284) affecting Windows Virtualization-Based Security (VBS) in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw allows a local attacker with low privileges to bypass security controls implemented by VBS, potentially leading to unauthorized access to sensitive information. The vulnerability has a CVSS 3.1 base score of 5.5, indicating medium severity, with attack vector local, low attack complexity, and no user interaction required. Microsoft has released an official fix to address this issue.
Potential Impact
An attacker with limited privileges on a vulnerable Windows 10 Version 1809 system could bypass VBS security features, potentially gaining unauthorized access to sensitive data or resources protected by virtualization-based security. The vulnerability does not impact system integrity or availability directly and requires local access.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. It is recommended to apply the security update provided by Microsoft as detailed in their advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21340 to remediate this issue.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- microsoft
- Date Reserved
- 2024-12-11T00:29:48.352Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21340","vendor":"Microsoft"}]
Threat ID: 68c0bd529ed239a66badebf1
Added to database: 09/09/2025, 23:50:42 UTC
Last enriched: 06/10/2026, 09:57:00 UTC
Last updated: 07/08/2026, 10:28:16 UTC
Views: 188
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