Microsoft Windows: Elevation of privilege in Windows Kernel-Mode Drivers

Summary

An integer overflow or wraparound in the Windows Kernel-Mode Drivers component allows a locally authorized attacker to elevate privileges. An attacker needs a low-privileged account on the affected system and no user interaction is required. The main risk for organisations is that an attacker who already has code running as a normal user can gain SYSTEM rights, especially on shared PCs, terminal servers and multi-user machines.

Affected

• Windows 10 Version 1607 (10.0.14393.0 to before 10.0.14393.9612)
• Windows 10 Version 1809, 21H2, 22H2
• Windows 11 Version 23H2, 24H2, 25H2, 26H1, 26H2
• Windows Server 2012 and 2012 R2 (including Server Core)
• Windows Server 2016 and later Server versions listed in the Microsoft advisory
• Exact affected build ranges per version: see the Microsoft Security Update Guide, as sources conflict on some fixed builds

Fixed in

• Windows 10 Version 1607: build 10.0.14393.9612 according to the CNA record; verify on the Microsoft Security Update Guide
• Other versions: install the October 2026 cumulative update for each build; the fixed build numbers differ between sources and must be confirmed on the Microsoft advisory

Workaround

• No vendor workaround known. Installing the update is the fix.
• Generic mitigations: apply least-privilege principles to user accounts, limit local logon rights and restrict who can run code on shared systems.

Exploitation

• Microsoft rates the exploit code maturity as Unproven and states the vulnerability is not exploited.
• No public proof-of-concept found in the research.
• Not listed in the CISA KEV catalog in the checked snapshot; recheck the catalog directly.
• Ratings differ: VulDB rates it very critical, Microsoft rates it Important.

Our recommendation

• Deploy the October 2026 cumulative update to all in-scope Windows builds, starting with terminal servers (RDS) and shared or multi-user systems.
• Verify the patched build on each host against the Microsoft Security Update Guide.
• Check whether Windows 10 Version 1607 is still in use and plan an upgrade, as it is end of life.
• Monitor endpoints for anomalous kernel-mode activity and restrict local code execution where possible.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• Microsoft Security Update Guide: CVE-2026-96915 msrc.microsoft.com
• Vulners: CNA record CVE-2026-96915 vulners.com
• OpenCVE: CVE-2026-96915 app.opencve.io
• Strix: CVE-2026-96915 www.strix.ai
• VulDB: CVE-2026-96915 vuldb.com
• VulDB: vulnerability 419643 vuldb.com

Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 2 Nov 2026, 00:44.