CVE-2026-21247: CWE-20: Improper Input Validation in Microsoft Windows 10 Version 1607
Improper input validation in Windows Hyper-V allows an authorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability stems from improper input validation in Windows Hyper-V on Windows 10 Version 1607 (build 10.0.14393.0). It enables an attacker with local privileges and user interaction to execute arbitrary code, potentially leading to full compromise of the affected system. The CVSS v3.1 base score is 7.3, indicating high severity, with attack vector local, low attack complexity, low privileges required, and user interaction needed. Microsoft has published an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an authorized local attacker to execute arbitrary code on the affected system, impacting confidentiality, integrity, and availability. This could lead to full system compromise if exploited.
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-2026-21247 to remediate this vulnerability.
CVE-2026-21247: CWE-20: Improper Input Validation in Microsoft Windows 10 Version 1607
Description
Improper input validation in Windows Hyper-V allows an authorized attacker to execute code locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability stems from improper input validation in Windows Hyper-V on Windows 10 Version 1607 (build 10.0.14393.0). It enables an attacker with local privileges and user interaction to execute arbitrary code, potentially leading to full compromise of the affected system. The CVSS v3.1 base score is 7.3, indicating high severity, with attack vector local, low attack complexity, low privileges required, and user interaction needed. Microsoft has published an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an authorized local attacker to execute arbitrary code on the affected system, impacting confidentiality, integrity, and availability. This could lead to full system compromise if exploited.
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-2026-21247 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-11T21:02:05.736Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21247","vendor":"Microsoft"}]
Threat ID: 698b76004b57a58fa120a01e
Added to database: 2/10/2026, 6:16:32 PM
Last enriched: 5/12/2026, 5:12:30 AM
Last updated: 5/22/2026, 8:33:21 PM
Views: 86
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