CVE-2026-85856: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607
Description
CVE-2026-85856 is a heap-based buffer overflow vulnerability in Windows Internet Connection Sharing (ICS) affecting multiple versions of Microsoft Windows 10, including Version 1607. This flaw allows an authorized attacker on an adjacent network to execute arbitrary code. The vulnerability has a high severity rating and has been officially fixed by Microsoft.
CVSS v3.1
Score 7.1high
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-2026-85856) involves a heap-based buffer overflow in the Windows Internet Connection Sharing (ICS) component. An attacker with limited privileges and access to an adjacent network can exploit this flaw to execute arbitrary code, potentially leading to full system compromise. The vulnerability affects multiple Windows 10 versions, including Version 1607 and several subsequent builds, as specified by the affected version ranges. Microsoft has released an official fix addressing this issue.
Potential Impact
Successful exploitation allows an attacker with limited privileges on an adjacent network to execute arbitrary code with high impact on confidentiality, integrity, and availability of the affected system. This could lead to system compromise or denial of service.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. Users and administrators should apply the security updates provided by Microsoft to the affected Windows 10 versions to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-04T18:15:10.738Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85856","vendor":"Microsoft"}]
Threat ID: 6ace85462cdf04f6569fec4e
Added to database: 10/13/2026, 19:23:50 UTC
Last enriched: 10/14/2026, 03:04:54 UTC
Last updated: 10/14/2026, 03:04:54 UTC
Views: 2
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