CVE-2026-85817: CWE-807: Reliance on Untrusted Inputs in a Security Decision in Microsoft Windows 10 Version 1607
Description
CVE-2026-85817 is a high-severity vulnerability in Microsoft Windows 10 Version 1607 and related builds, involving reliance on untrusted inputs in a security decision within Windows PowerShell. This flaw allows an unauthorized attacker to execute code remotely over a network. The vulnerability affects multiple Windows 10 builds prior to specific patch versions. An official fix is available from Microsoft.
CVSS v3.1
Score 8.8high
Affected software
Microsoft
Windows 10 Version 1607
Microsoft
Windows 10 Version 1809
Microsoft
Windows 10 Version 21H2
Microsoft
Windows 10 Version 22H2
Microsoft
Windows 11 version 23H2
Microsoft
Windows 11 Version 23H2
Microsoft
Windows 11 Version 24H2
Microsoft
Windows 11 Version 25H2
Microsoft
Windows 11 version 26H1
Microsoft
Windows 11 Version 26H2
Microsoft
Windows Server 2012
Microsoft
Windows Server 2012 (Server Core installation)
Microsoft
Windows Server 2012 R2
Microsoft
Windows Server 2012 R2 (Server Core installation)
Microsoft
Windows Server 2016
Microsoft
Windows Server 2016 (Server Core installation)
Microsoft
Windows Server 2019
Microsoft
Windows Server 2019 (Server Core installation)
Microsoft
Windows Server 2022
Microsoft
Windows Server 2025
Microsoft
Windows Server 2025 (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-85817) involves Windows PowerShell in Microsoft Windows 10 Version 1607 and other related versions relying on untrusted inputs when making security decisions. This flaw enables an attacker without privileges to execute arbitrary code remotely over a network. The CVSS 3.1 score is 8.8 (high severity), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability. Multiple affected Windows 10 versions are identified with specific build ranges. Microsoft has released an official fix for this vulnerability.
Potential Impact
An attacker can remotely execute arbitrary code on affected Windows 10 systems without needing privileges, potentially leading to full system compromise including confidentiality, integrity, and availability impacts. This could allow unauthorized control over the affected system.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. It is recommended to apply the security updates provided by Microsoft as detailed in their advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85817 to remediate this issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-04T18:12:22.898Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85817","vendor":"Microsoft"}]
Threat ID: 6ace853e2cdf04f6569fe859
Added to database: 10/13/2026, 19:23:42 UTC
Last enriched: 10/14/2026, 03:33:47 UTC
Last updated: 10/14/2026, 03:33:47 UTC
Views: 2
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