Microsoft Windows: Elevation of privilege in Modern Device Management (MDM)
Summary
A missing authentication check for a critical function in the Windows Modern Device Management (MDM) component allows an authorized local user to elevate privileges. An attacker needs local access and low-privileged credentials, and no user interaction is required. Successful exploitation can lead to high impact on confidentiality, integrity and availability of the affected system.
Affected
- Windows 10 Version 21H2: builds 10.0.19044.0 to below 10.0.19044.7807; - Windows 10 Version 22H2: builds 10.0.19045.0 to below 10.0.19045.7807; - Windows 11 Version 23H2: builds 10.0.22631.0 to below 10.0.22631.7652; - Windows 11 Version 24H2: builds 10.0.26100.0 to below 10.0.26100.9711; - Windows 11 Version 25H2: builds 10.0.26200.0 to below 10.0.26200.9711; - Windows 11 Version 26H1: builds 10.0.28000.0 to below 10.0.28000.3231; - Windows 11 Version 26H2: builds 10.0.26300.0 to below 10.0.26300.9711; - Windows Server 2022: builds 10.0.20348.0 to below 10.0.20348.5761; - Windows Server 2025 (including Server Core): builds 10.0.26100.0 to below 10.0.26100.33650
Fixed in
- Windows 10 Version 21H2: 10.0.19044.7807 or later; - Windows 10 Version 22H2: 10.0.19045.7807 or later; - Windows 11 Version 23H2: 10.0.22631.7652 or later; - Windows 11 Version 24H2: 10.0.26100.9711 or later; - Windows 11 Version 25H2: 10.0.26200.9711 or later; - Windows 11 Version 26H1: 10.0.28000.3231 or later; - Windows 11 Version 26H2: 10.0.26300.9711 or later; - Windows Server 2022: 10.0.20348.5761 or later; - Windows Server 2025: 10.0.26100.33650 or later
Workaround
Unknown. No workaround is described in the sources reviewed; check the Microsoft advisory.
Exploitation
- CISA SSVC: exploitation none, not automatable, total technical impact; - Not listed in the CISA KEV catalog; - EPSS below 1 percent; - No public proof of concept found in the sources reviewed.
Our recommendation
- Identify Windows devices, especially Windows 10 Version 21H2, and confirm the installed build meets the fixed version; - Install the October 2026 security update on priority for shared, kiosk and high-risk endpoints; - For Windows 10 Version 21H2, verify that the device still receives security updates (LTSC or ESU), otherwise plan an upgrade; - Review local administrator rights and remove unneeded local accounts; - Monitor the Microsoft advisory for workaround changes or exploitation reports.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Modern Device Management (MDM)
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5126655, KB5126657, KB5126646, KB5127648, KB5126653, KB5127646
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-83654 msrc.microsoft.com
- Vulners: CVE.org CNA record mirror CVE-2026-83654 vulners.com
- OpenCVE: CVE-2026-83654 app.opencve.io
- Vulners NVD record CVE-2026-83654 vulners.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, 03:27.
Original description (NVD)
Missing authentication for critical function in Windows Modern Device Management (MDM) 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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