CVE-2026-20816: Windows Installer Elevation of Privilege Vulnerability
Time-of-check time-of-use (toctou) race condition in Windows Installer allows an authorized attacker to elevate privileges locally.
Other sources
Windows Installer Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.3.9600.22968Patch KB5073696 - Upgrade
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Fixed in 6.2.9200.25868Patch KB5073698 - Upgrade
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Fixed in 6.1.7601.28117Patch KB5073699 - Upgrade
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Fixed in 6.0.6003.23717Patch KB5073700 - Upgrade
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Fixed in 10.0.14393.8783Patch KB5073722 - Upgrade
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Fixed in 10.0.26100.32230Patch KB5073379 - Upgrade
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Fixed in 10.0.26100.7623Patch KB5074109 - Upgrade
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Fixed in 10.0.26200.7623Patch KB5074109 - Upgrade
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Fixed in 10.0.22631.6491Patch KB5073455 - Upgrade
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Fixed in 10.0.25398.2092Patch KB5073450 - Upgrade
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Fixed in 10.0.19045.6809Patch KB5073724 - Upgrade
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Fixed in 10.0.19044.6809Patch KB5073724 - Upgrade
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Fixed in 10.0.20348.4648Patch KB5073457 - Upgrade
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Fixed in 10.0.17763.8276Patch KB5073723
Event History
Frequently Asked Questions
What is the severity of CVE-2026-20816?
CVE-2026-20816 is classified as an Elevation of Privilege vulnerability.
How do I fix CVE-2026-20816?
To fix CVE-2026-20816, apply the relevant security updates provided by Microsoft for affected products.
What products are affected by CVE-2026-20816?
CVE-2026-20816 affects various versions of Windows Server and Windows 10, including 2008, 2012, 2016, and 2022.
Can CVE-2026-20816 be exploited remotely?
No, CVE-2026-20816 can only be exploited by an authorized user on the local system.
What are the consequences of CVE-2026-20816 exploitation?
Exploitation of CVE-2026-20816 can allow an attacker to elevate their privileges on the affected system.