Local code execution via Win32K GRFX race
Published Sep 9, 2025 · Updated Feb 26, 2026
Local code execution in Windows Win32K GRFX allows local users with low privileges to execute code on affected Windows builds. Win32K GRFX fails to synchronize concurrent access to a shared resource, creating a race that can leave code using freed memory. Exploitation requires local low-privilege access and winning a high-complexity timing race; successful exploitation executes code in a higher-privileged security context.
Summary
What happened
Local code execution in Windows Win32K GRFX allows local users with low privileges to execute code on affected Windows builds. Win32K GRFX fails to synchronize concurrent access to a shared resource, creating a race that can leave code using freed memory. Exploitation requires local low-privilege access and winning a high-complexity timing race; successful exploitation executes code in a higher-privileged security context.
The record
- CVE
- CVE-2025-55228
- Published
- Sep 9, 2025
- Updated
- Feb 26, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-416, CWE-362, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 9, 2025CVE publishedPublication date reported by the CVE source.
- Feb 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.26100.0 <10.0.26100.6584
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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