CVE-2026-21237: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') in Microsoft Windows 10 Version 21H2
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability involves a race condition (CWE-362) in Windows Subsystem for Linux on Windows 10 Version 21H2 (build 10.0.19044.0). Improper synchronization during concurrent execution of shared resources can be exploited by an authorized local attacker to gain elevated privileges. The issue is recognized by Microsoft and has been assigned CVE-2026-21237. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an authorized local user to elevate their privileges, potentially gaining higher system rights than intended. This could lead to full system compromise depending on the privileges gained. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector.
Mitigation Recommendations
An official patch is available from Microsoft and should be applied promptly to remediate this vulnerability. Refer to the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21237 for patch details and installation instructions.
CVE-2026-21237: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') in Microsoft Windows 10 Version 21H2
Description
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a race condition (CWE-362) in Windows Subsystem for Linux on Windows 10 Version 21H2 (build 10.0.19044.0). Improper synchronization during concurrent execution of shared resources can be exploited by an authorized local attacker to gain elevated privileges. The issue is recognized by Microsoft and has been assigned CVE-2026-21237. Microsoft has released an official fix to remediate this vulnerability.
Potential Impact
Successful exploitation allows an authorized local user to elevate their privileges, potentially gaining higher system rights than intended. This could lead to full system compromise depending on the privileges gained. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector.
Mitigation Recommendations
An official patch is available from Microsoft and should be applied promptly to remediate this vulnerability. Refer to the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21237 for patch details and installation instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-11T21:02:05.734Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21237","vendor":"Microsoft"}]
Threat ID: 698b75ff4b57a58fa1209fe1
Added to database: 2/10/2026, 6:16:31 PM
Last enriched: 5/12/2026, 5:10:55 AM
Last updated: 5/22/2026, 5:47:00 PM
Views: 154
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