CVE-2026-85791: Windows Encrypting File System (EFS) Elevation of Privilege Vulnerability
Heap-based buffer overflow in Windows Encrypting File System (EFS) allows an authorized attacker to elevate privileges locally.
Other sources
Windows Encrypting File System (EFS) Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.26300.9711Patch KB5127648 - Upgrade
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Fixed in 10.0.14393.9612Patch KB5126868 - 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 10.0.22631.7652Patch KB5126653 - 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 10.0.26200.9711Patch 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 10.0.26100.33650Patch KB5126646 - Upgrade
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Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
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Fixed in 10.0.17763.9376Patch KB5126651
Event History
Frequently Asked Questions
Who is exposed to this vulnerability?
Systems running the listed Microsoft Windows client or server products are in scope. Exploitation is local, so exposure depends on an attacker already having authorized access to the affected system.
What access and conditions does an attacker need?
An attacker must be authorized and able to execute an exploit locally. The available data rates attack complexity as high and does not require user interaction.
What could successful exploitation allow?
Successful exploitation could allow an authorized local attacker to elevate privileges. The reported impact includes high confidentiality, integrity, and availability effects.
Is there evidence of active exploitation?
The supplied data marks exploit maturity as unknown. It does not provide evidence that this vulnerability is being exploited in the wild.