CVE-2026-56176: Windows Win32k Elevation of Privilege Vulnerability
Out-of-bounds read in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally.
Other sources
Windows Win32k 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 6.3.9600.23291Patch KB5099444 - Upgrade
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Fixed in 10.0.14393.9339Patch KB5099535 - Upgrade
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Fixed in 6.2.9200.26226Patch KB5099445 - Upgrade
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Fixed in 10.0.28000.2525Patch KB5101649 - Upgrade
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Fixed in 10.0.26100.33158Patch KB5099536 - Upgrade
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Fixed in 10.0.19045.7548Patch KB5099539 - Upgrade
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Fixed in 10.0.26100.8875Patch KB5101650 - Upgrade
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Fixed in 10.0.26200.8875Patch KB5101650 - Upgrade
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Fixed in 10.0.19044.7548Patch KB5099539 - Upgrade
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Fixed in 10.0.17763.9020Patch KB5099538 - Upgrade
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Fixed in 10.0.20348.5386Patch KB5099540 - Upgrade
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Fixed in 16.111.26071215 - Upgrade
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Fixed in 16.0.20228.20042
Event History
Frequently Asked Questions
Who is exposed to this vulnerability?
Systems running the listed Microsoft Windows 10, Windows 11, or Windows Server versions are in scope. Exploitation is local, so the attacker must already be able to execute code on the affected system.
What access does an attacker need to exploit it?
The attacker needs authorized local access with low privileges. No user interaction is required.
What is the likely impact of successful exploitation?
Successful exploitation can elevate the attacker's privileges on the local system. The supplied severity vector indicates high impacts to confidentiality, integrity, and availability.
What should organizations do if affected?
Apply the available patch for CVE-2026-56176. Until patching is complete, prioritize limiting untrusted local code execution and restricting low-privileged access to affected systems.