CVE-2026-66799: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Heap-based buffer overflow in Windows Key Guard allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability involves a heap-based buffer overflow in the Windows Key Guard component of Windows 10 Version 1607 (build 10.0.14393.0). An authorized attacker with local access can exploit this flaw to elevate their privileges. The vulnerability is tracked as CWE-122. Microsoft has published an official fix to remediate the issue. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation of this vulnerability could allow an authorized local attacker to gain elevated privileges, potentially leading to full system compromise. The confidentiality, integrity, and availability of the affected system could be severely impacted.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66799 to remediate this vulnerability.
CVE-2026-66799: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Description
Heap-based buffer overflow in Windows Key Guard allows an authorized attacker to elevate privileges locally.
CVSS v3.1
Score 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a heap-based buffer overflow in the Windows Key Guard component of Windows 10 Version 1607 (build 10.0.14393.0). An authorized attacker with local access can exploit this flaw to elevate their privileges. The vulnerability is tracked as CWE-122. Microsoft has published an official fix to remediate the issue. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation of this vulnerability could allow an authorized local attacker to gain elevated privileges, potentially leading to full system compromise. The confidentiality, integrity, and availability of the affected system could be severely impacted.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66799 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-07-27T19:02:26.600Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66799","vendor":"Microsoft"}]
Threat ID: 6a7b5835bf8831d5391564ff
Added to database: 08/11/2026, 17:13:25 UTC
Last enriched: 08/11/2026, 19:13:50 UTC
Last updated: 08/12/2026, 00:12:10 UTC
Views: 3
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