CVE-2026-20934
Unknown Unknown - Not Provided
Race Condition in Windows SMB Server Enables Privilege Escalation

Publication date: 2026-01-13

Last updated on: 2026-01-13

Assigner: Microsoft Corporation

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.
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Meta Information
Published
2026-01-13
Last Modified
2026-01-13
Generated
2026-06-16
AI Q&A
2026-01-14
EPSS Evaluated
2026-06-15
NVD
CVE-2026-20934
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
microsoft windows_smb_server *
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-362 The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
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Executive Summary

This vulnerability is a race condition in the Windows SMB Server where concurrent execution using a shared resource occurs without proper synchronization. This flaw allows an authorized attacker to elevate their privileges over a network. [1]

Impact Analysis

An attacker who is authorized on the network can exploit this vulnerability to gain higher privileges than they should have, potentially allowing them to perform unauthorized actions or access sensitive information. [1]

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