CVE-2026-40399: CWE-121: Stack-based Buffer Overflow in Microsoft Windows 10 Version 1607
Stack-based buffer overflow in Windows TCP/IP allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability involves a stack-based buffer overflow in the TCP/IP implementation of Windows 10 Version 1607. An attacker with local authorized access can exploit this flaw to elevate their privileges, potentially gaining higher-level control over the system. The vulnerability is tracked as CWE-121 and has been assigned CVE-2026-40399. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, which can lead to full control over the affected system. The vulnerability impacts confidentiality, integrity, and availability, as indicated by the CVSS vector (C:H/I:H/A:H). There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40399 to remediate this vulnerability.
CVE-2026-40399: CWE-121: Stack-based Buffer Overflow in Microsoft Windows 10 Version 1607
Description
Stack-based buffer overflow in Windows TCP/IP allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a stack-based buffer overflow in the TCP/IP implementation of Windows 10 Version 1607. An attacker with local authorized access can exploit this flaw to elevate their privileges, potentially gaining higher-level control over the system. The vulnerability is tracked as CWE-121 and has been assigned CVE-2026-40399. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, which can lead to full control over the affected system. The vulnerability impacts confidentiality, integrity, and availability, as indicated by the CVSS vector (C:H/I:H/A:H). There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40399 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-04-13T00:27:50.797Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40399","vendor":"Microsoft"}]
Threat ID: 6a036554cbff5d861008c96e
Added to database: 5/12/2026, 5:37:24 PM
Last enriched: 5/12/2026, 6:51:37 PM
Last updated: 5/13/2026, 4:49:44 AM
Views: 2
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