CVE-2026-40403: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Heap-based buffer overflow in Windows Win32K - GRFX allows an authorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability involves a heap-based buffer overflow in the Win32K graphics subsystem of Windows 10 Version 1607. An attacker with local authorized access can exploit this flaw to execute arbitrary code, potentially gaining elevated privileges and compromising system security. The vulnerability is tracked as CWE-122 and has been assigned CVE-2026-40403. Microsoft has released an official fix to remediate this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to local code execution with elevated privileges, resulting in full compromise of the affected system's confidentiality, integrity, and availability. There are no known exploits in the wild at the time of publication.
Mitigation Recommendations
An official patch is available from Microsoft to remediate this vulnerability. It is strongly recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40403 to protect affected systems running Windows 10 Version 1607.
CVE-2026-40403: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Description
Heap-based buffer overflow in Windows Win32K - GRFX allows an authorized attacker to execute code locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a heap-based buffer overflow in the Win32K graphics subsystem of Windows 10 Version 1607. An attacker with local authorized access can exploit this flaw to execute arbitrary code, potentially gaining elevated privileges and compromising system security. The vulnerability is tracked as CWE-122 and has been assigned CVE-2026-40403. Microsoft has released an official fix to remediate this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to local code execution with elevated privileges, resulting in full compromise of the affected system's confidentiality, integrity, and availability. There are no known exploits in the wild at the time of publication.
Mitigation Recommendations
An official patch is available from Microsoft to remediate this vulnerability. It is strongly recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40403 to protect affected systems running Windows 10 Version 1607.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-04-13T00:27:50.798Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40403","vendor":"Microsoft"}]
Threat ID: 6a036557cbff5d861008c9b8
Added to database: 5/12/2026, 5:37:27 PM
Last enriched: 5/12/2026, 6:51:19 PM
Last updated: 5/13/2026, 4:51:47 AM
Views: 40
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