CVE-2026-20816
Unknown Unknown - Not Provided
TOCTOU Race Condition in Windows Installer Enables Local Privilege Escalation

Publication date: 2026-01-13

Last updated on: 2026-01-13

Assigner: Microsoft Corporation

Description
Time-of-check time-of-use (toctou) race condition in Windows Installer allows an authorized attacker to elevate privileges locally.
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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-2026-20816
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
microsoft windows_installer *
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-367 The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
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Executive Summary

This vulnerability is a time-of-check time-of-use (toctou) race condition in Windows Installer that allows an authorized attacker to elevate their privileges locally on the affected system. [1]

Impact Analysis

An attacker who already has some level of authorization on the system can exploit this vulnerability to gain higher privileges, potentially allowing them to perform actions that require elevated rights, which could compromise system security and integrity. [1]

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