CVE-2026-20921
7.5 HIGHConcurrent execution using shared resource with improper synchronization ('race condition') in Windows SMB Server allows an authorized at...
Published: 2026-01-13 · Last updated: 2026-05-26
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-362
Affected products
| Vendor | Product |
|---|---|
| microsoft | windows_10_1607, windows_10_1809, windows_10_21h2 |
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.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2026-20921
- [Vendor advisory]https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20921
- [Other]https://www.vicarius.io/vsociety/posts/cve-2026-20921-detection-script-race-condition-vulnerability-in-windows-smb-server
- [Other]https://www.vicarius.io/vsociety/posts/cve-2026-20921-remediation-script-race-condition-vulnerability-in-windows-smb-server
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