CVE-2026-20816: CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition in Microsoft Windows 10 Version 1607
Time-of-check time-of-use (toctou) race condition in Windows Installer allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability is a TOCTOU race condition (CWE-367) in the Windows Installer component of Windows 10 Version 1607 (build 10.0.14393.0). It allows an attacker with local authorized access to exploit the timing window between checking a condition and using a resource, resulting in privilege escalation. The CVSS 3.1 vector indicates low attack complexity, low privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The vulnerability is confirmed published and a patch is available.
Potential Impact
An authorized local attacker can exploit this race condition to elevate their privileges on the affected Windows 10 system. This could lead to full system compromise, including unauthorized access to sensitive data and system control. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
A patch is available for this vulnerability and should be applied promptly to affected systems running Windows 10 Version 1607 (build 10.0.14393.0). No additional mitigation steps are indicated beyond applying the official fix.
CVE-2026-20816: CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition in Microsoft Windows 10 Version 1607
Description
Time-of-check time-of-use (toctou) race condition in Windows Installer allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability is a TOCTOU race condition (CWE-367) in the Windows Installer component of Windows 10 Version 1607 (build 10.0.14393.0). It allows an attacker with local authorized access to exploit the timing window between checking a condition and using a resource, resulting in privilege escalation. The CVSS 3.1 vector indicates low attack complexity, low privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The vulnerability is confirmed published and a patch is available.
Potential Impact
An authorized local attacker can exploit this race condition to elevate their privileges on the affected Windows 10 system. This could lead to full system compromise, including unauthorized access to sensitive data and system control. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
A patch is available for this vulnerability and should be applied promptly to affected systems running Windows 10 Version 1607 (build 10.0.14393.0). No additional mitigation steps are indicated beyond applying the official fix.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-03T05:54:20.373Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668adba60475309f9adf8e
Added to database: 1/13/2026, 6:11:39 PM
Last enriched: 4/3/2026, 12:41:41 PM
Last updated: 5/10/2026, 9:08:07 AM
Views: 174
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