CVE-2026-20921: 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 involves a race condition (CWE-362) in the Windows SMB Server on Windows 10 Version 1607 (build 10.0.14393.0). Due to improper synchronization when concurrently accessing shared resources, an authorized attacker can exploit this flaw remotely over the network to elevate their privileges. The CVSS 3.1 base score is 7.5, reflecting high impact on confidentiality, integrity, and availability. The attack complexity is high and requires low privileges but no user interaction. Microsoft has released a patch to remediate this vulnerability.
Potential Impact
Successful exploitation of this race condition vulnerability allows an attacker with authorized network access to elevate their privileges on the affected system. This can lead to full compromise of the system's confidentiality, integrity, and availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 1607 (build 10.0.14393.0) to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-20921: 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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a race condition (CWE-362) in the Windows SMB Server on Windows 10 Version 1607 (build 10.0.14393.0). Due to improper synchronization when concurrently accessing shared resources, an authorized attacker can exploit this flaw remotely over the network to elevate their privileges. The CVSS 3.1 base score is 7.5, reflecting high impact on confidentiality, integrity, and availability. The attack complexity is high and requires low privileges but no user interaction. Microsoft has released a patch to remediate this vulnerability.
Potential Impact
Successful exploitation of this race condition vulnerability allows an attacker with authorized network access to elevate their privileges on the affected system. This can lead to full compromise of the system's confidentiality, integrity, and availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 1607 (build 10.0.14393.0) to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.335Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668ae3a60475309f9ae1c3
Added to database: 1/13/2026, 6:11:47 PM
Last enriched: 4/3/2026, 12:49:11 PM
Last updated: 5/8/2026, 10:20:50 PM
Views: 266
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