Microsoft Windows 10 Version 1607: Local privilege escalation in Windows Overlay Filter
Summary
A race condition (CWE-362, CWE-416) in the Windows Overlay Filter component allows an authorized local user to elevate privileges. The attacker needs local access and low privileges, and the attack is rated as high complexity. Successful exploitation could lead to full compromise of confidentiality, integrity and availability on the affected system. The flaw is not remotely exploitable and no exploitation has been reported.
Affected
- Windows 10 Version 1607 (x86 and x64), builds 10.0.14393.0 to before 10.0.14393.9612
- Windows Server 2016 incl. Server Core installation, builds 10.0.14393.0 to before 10.0.14393.9612
- The CVE record also lists Windows 10 1809 to 22H2, Windows 11 23H2 to 26H2, and Windows Server 2012 R2 and 2019
Fixed in
- Windows 10 Version 1607 and Server 2016: build 10.0.14393.9612 or later
- Fixed builds for other products are listed in the MSRC advisory
- KB number for Windows 10 1607: Unknown.
Workaround
Unknown. No workaround or mitigation was found in the sources.
Exploitation
- No evidence of active exploitation in the wild; not listed in the CISA KEV catalog.
- No public proof-of-concept exploit found.
- CISA SSVC: exploitation none, not automatable, total technical impact.
- NVD base score 7.0 (CVSS 3.1: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H).
Our recommendation
- Inventory all Windows 10 1607 and Server 2016 systems and check whether Microsoft still supports them.
- Install the October 2026 cumulative update that brings the build to 10.0.14393.9612 or later; verify the KB number on the MSRC advisory first.
- If a system cannot be patched, plan replacement or isolation and limit local logon to trusted accounts.
- Give extra attention to shared workstations, terminal servers and file servers with many low-privileged accounts.
- Recheck NVD and MSRC for changes to the score, fixes or exploit status.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Overlay Filter
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5127648, KB5126651, KB5126655, KB5126657, KB5126646, KB5126653
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-83879 msrc.microsoft.com
- NVD mirror (Vulners): CVE-2026-83879 vulners.com
- VulDB: CVE-2026-83879 vuldb.com
- OpenCVE: CVE-2026-83879 app.opencve.io
- Strix: CVE-2026-83879 www.strix.ai
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 4 Nov 2026, 08:04.
Original description (NVD)
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Overlay Filter allows an authorized attacker to elevate privileges locally.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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