CVE-2026-20919: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') in Microsoft Windows 10 Version 1607
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows SMB Server allows an authorized attacker to elevate privileges over a network.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20919) involves a race condition (CWE-362) in the Windows SMB Server on Windows 10 Version 1607 (build 10.0.14393.0). The flaw arises from improper synchronization when multiple processes concurrently access shared resources, enabling an authorized attacker to elevate privileges remotely over the network. The CVSS v3.1 base score is 7.5, reflecting high impact on confidentiality, integrity, and availability. Microsoft has published an official fix to remediate this vulnerability.
Potential Impact
An authorized attacker can exploit this race condition vulnerability remotely via the SMB protocol to elevate their privileges on the affected Windows 10 Version 1607 system. Successful exploitation could lead to full system compromise, affecting confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Microsoft has released an official patch to fix this vulnerability. Users and administrators should apply the provided security update for Windows 10 Version 1607 as detailed in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20919. Applying this update mitigates the risk of privilege escalation via this race condition.
CVE-2026-20919: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') in Microsoft Windows 10 Version 1607
Description
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows SMB Server allows an authorized attacker to elevate privileges over a network.
CVSS v3.1
Score 7.5high
Affected software
Microsoft
Windows 10 Version 1607
Microsoft
Windows 10 Version 1809
Microsoft
Windows 10 Version 21H2
Microsoft
Windows 10 Version 22H2
Microsoft
Windows 11 version 23H2
Microsoft
Windows 11 Version 23H2
Microsoft
Windows 11 Version 24H2
Microsoft
Windows 11 Version 25H2
Microsoft
Windows Server 2012
Microsoft
Windows Server 2012 (Server Core installation)
Microsoft
Windows Server 2012 R2
Microsoft
Windows Server 2012 R2 (Server Core installation)
Microsoft
Windows Server 2016
Microsoft
Windows Server 2016 (Server Core installation)
Microsoft
Windows Server 2019
Microsoft
Windows Server 2019 (Server Core installation)
Microsoft
Windows Server 2022
Microsoft
Windows Server 2022, 23H2 Edition (Server Core installation)
Microsoft
Windows Server 2025
Microsoft
Windows Server 2025 (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20919) involves a race condition (CWE-362) in the Windows SMB Server on Windows 10 Version 1607 (build 10.0.14393.0). The flaw arises from improper synchronization when multiple processes concurrently access shared resources, enabling an authorized attacker to elevate privileges remotely over the network. The CVSS v3.1 base score is 7.5, reflecting high impact on confidentiality, integrity, and availability. Microsoft has published an official fix to remediate this vulnerability.
Potential Impact
An authorized attacker can exploit this race condition vulnerability remotely via the SMB protocol to elevate their privileges on the affected Windows 10 Version 1607 system. Successful exploitation could lead to full system compromise, affecting confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Microsoft has released an official patch to fix this vulnerability. Users and administrators should apply the provided security update for Windows 10 Version 1607 as detailed in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20919. Applying this update mitigates the risk of privilege escalation via this race condition.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.335Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20919","vendor":"Microsoft"}]
Threat ID: 69668ae1a60475309f9ae17e
Added to database: 01/13/2026, 18:11:45 UTC
Last enriched: 07/30/2026, 23:41:19 UTC
Last updated: 09/10/2026, 22:25:54 UTC
Views: 155
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