CVE-2026-21236: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Heap-based buffer overflow in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability involves a heap-based buffer overflow in the Windows Ancillary Function Driver for WinSock component of Windows 10 Version 1607 (build 10.0.14393.0). An authorized local attacker can exploit this flaw to elevate privileges, potentially gaining higher system rights. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability, as documented in their security update guide.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, which can lead to full control over the affected system. This impacts confidentiality, integrity, and availability of the system. No public exploits are currently known, reducing immediate risk, but the vulnerability remains critical until patched.
Mitigation Recommendations
Apply the official security update provided by Microsoft as detailed in their advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21236. This patch fully addresses the vulnerability. No additional mitigation steps are required beyond applying the official fix.
CVE-2026-21236: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Description
Heap-based buffer overflow in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a heap-based buffer overflow in the Windows Ancillary Function Driver for WinSock component of Windows 10 Version 1607 (build 10.0.14393.0). An authorized local attacker can exploit this flaw to elevate privileges, potentially gaining higher system rights. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability, as documented in their security update guide.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, which can lead to full control over the affected system. This impacts confidentiality, integrity, and availability of the system. No public exploits are currently known, reducing immediate risk, but the vulnerability remains critical until patched.
Mitigation Recommendations
Apply the official security update provided by Microsoft as detailed in their advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21236. This patch fully addresses the vulnerability. No additional mitigation steps are required beyond applying the official fix.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-11T21:02:05.734Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21236","vendor":"Microsoft"}]
Threat ID: 698b75ff4b57a58fa1209fde
Added to database: 2/10/2026, 6:16:31 PM
Last enriched: 5/12/2026, 5:10:50 AM
Last updated: 5/21/2026, 6:34:53 PM
Views: 121
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