CVE-2026-33840: Win32k Elevation of Privilege Vulnerability
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally.
Other sources
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 10.0.26100.8457Fixed in 10.0.26100.8390Patch KB5089466 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.8457Fixed in 10.0.26200.8390Patch KB5089466 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.32860Fixed in 10.0.26100.32772Patch KB5087423 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.2113Patch KB5089548
Event History
Frequently Asked Questions
What is the severity of CVE-2026-33840?
CVE-2026-33840 is rated as a high-severity vulnerability due to its potential for privilege escalation.
How do I fix CVE-2026-33840?
To fix CVE-2026-33840, it's recommended to apply the latest security updates provided by Microsoft for affected Windows 11 versions.
Which versions of Windows are affected by CVE-2026-33840?
CVE-2026-33840 affects specific builds of Windows 11, including versions 24H2, 25H2, and 26H1.
Can CVE-2026-33840 be exploited remotely?
CVE-2026-33840 requires local access for exploitation, meaning an attacker must have access to the physical or remote desktop session.
What can happen if CVE-2026-33840 is successfully exploited?
If successfully exploited, CVE-2026-33840 allows an attacker to elevate their privileges and gain increased control over the system.