CVE-2026-71339: Windows Installer Elevation of Privilege Vulnerability
Heap-based buffer overflow 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
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Fixed in 6.2.9200.26349Patch KB5123065 - Upgrade
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Fixed in 10.0.26100.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.14393.9512Patch KB5123099 - Upgrade
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Fixed in 10.0.26100.33438Patch KB5122871 - Upgrade
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Fixed in 10.0.28000.2954Patch KB5124012 - Upgrade
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Fixed in 10.0.22631.7582Patch KB5122880 - Upgrade
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Fixed in 10.0.26200.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.19045.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.19044.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.17763.9245Patch KB5122876 - Upgrade
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Fixed in 10.0.20348.5622Patch KB5122882 - Upgrade
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Fixed in 6.3.9600.23397Patch KB5123066
Event History
Frequently Asked Questions
Which Windows versions are listed as affected?
The affected software list includes Windows 10, Windows 11, Windows Server 2012 and 2012 R2, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.
What access does an attacker need before exploitation?
The CVSS vector indicates local access, low attack complexity, no user interaction, and high privileges required. This is therefore primarily a concern where an attacker already has authorized local access with significant privileges.
What is the potential impact after successful exploitation?
The CVSS metrics rate confidentiality, integrity, and availability impact as high, while scope is unchanged. Successful exploitation could therefore significantly affect the compromised Windows system without indicating impact beyond its security authority.