CVE-2026-87699: Winlogon Elevation of Privilege Vulnerability
Heap-based buffer overflow in Winlogon allows an authorized attacker to elevate privileges locally.
Other sources
Winlogon 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 6.2.9200.26434Patch KB5126835 - Upgrade
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Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
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Fixed in 10.0.26100.9711Patch KB5127648 - 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 10.0.26100.33650Patch KB5126646 - Upgrade
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Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.17763.9376Patch KB5126651 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7652Patch KB5126653 - 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
Event History
Frequently Asked Questions
Who is exposed to this issue?
Systems running the listed Microsoft Windows 10, Windows 11, and Windows Server versions are affected. Exploitation is local rather than network-based.
What access does an attacker need to exploit it?
An attacker must already be authorized on the target system and have local access. No user interaction is required.
What is the potential impact of successful exploitation?
A successful exploit can elevate the attacker's privileges and affect confidentiality, integrity, and availability on the affected system.