CVE-2026-85366: 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
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.14393.9612Patch KB5126868 - Upgrade
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Fixed in 10.0.26300.9711Patch KB5127648 - Upgrade
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Fixed in 6.2.9200.26434Patch KB5126835 - Upgrade
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Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
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Fixed in 10.0.17763.9376Patch KB5126651 - Upgrade
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Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
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Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19044.7807Patch KB5126657 - Upgrade
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Fixed in 10.0.20348.5761Patch KB5126655
Event History
Frequently Asked Questions
What level of access does an attacker need before exploitation?
The attacker must already have local access and low privileges on the affected system. The vulnerability is not rated as remotely exploitable.
Does exploitation require user interaction?
No. The CVSS vector indicates that no user interaction is required once an authorized local attacker has the necessary access.
Which Windows versions are listed as affected?
Affected software includes Windows 10, Windows 11, Windows Server 2012, Windows Server 2012 R2, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.