Microsoft Windows Bluetooth Driver: Elevation of privilege via race condition

Summary

A race condition (CWE-362) in the Microsoft Bluetooth Driver allows an authorized local user to elevate privileges. The attacker needs a valid local logon and must win a timing condition, so the attack complexity is high. Remote exploitation is not possible from the network.

Affected

• Windows 10 Version 1809 and Windows Server 2019 (including Server Core): builds 10.0.17763.0 before 10.0.17763.9376
• Windows 10 Version 21H2: builds 10.0.19044.0 before 10.0.19044.7807
• Windows 10 Version 22H2: builds 10.0.19045.0 before 10.0.19045.7807
• Windows 11 Version 23H2: builds 10.0.22631.0 before 10.0.22631.7652
• Windows 11 Version 24H2 and 25H2: builds 10.0.26100.0 before 10.0.26100.9711 and 10.0.26200.0 before 10.0.26200.9711
• Windows 11 Version 26H1: builds 10.0.28000.0 before 10.0.28000.3231
• Windows 11 Version 26H2: builds 10.0.26300.0 before 10.0.26300.9711
• Windows Server 2022: builds 10.0.20348.0 before 10.0.20348.5761
• Windows Server 2025 (including Server Core): builds 10.0.26100.0 before 10.0.26100.33650

Fixed in

• Windows 10 Version 1809 and Windows Server 2019: build 10.0.17763.9376 or later (KB5126651, reported; confirm the CVE mapping on the MSRC page)
• Other affected versions: the fixed builds listed under affected, via the October 2026 security updates
• Vendor fix details: see the MSRC Security Update Guide

Workaround

• No vendor workaround is known. Installing the security update is the fix.
• Disable Bluetooth on devices that do not need it (general hardening, not from a vendor source).
• Limit local logon to trusted users (general hardening, not from a vendor source).

Exploitation

• Microsoft CVSS exploit maturity: Unproven (E:U).
• CISA SSVC: exploitation none, not automatable, total technical impact.
• EPSS about 0.16 percent.
• No public proof of concept found. No evidence of exploitation in the wild found.

Our recommendation

• Install the October 2026 security update on all affected Windows 10 1809, Windows Server 2019 and other listed systems, after confirming the CVE mapping on the MSRC page.
• Prioritise shared PCs, kiosks, terminals and devices where several people or contractors share one account.
• Disable Bluetooth where it is not required and restrict local accounts.
• If you run on-premises Exchange, test the reported OWA sign-in and mail-sending issue after KB5126651 before rollout.
• Confirm that Windows 10 1809 devices are on a supported servicing path.

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

• MSRC Security Update Guide advisory msrc.microsoft.com
• KB5126651 Windows 10 1809 security update (Microsoft Support) support.microsoft.com
• Windows 10 1809 and Server 2019 release health status learn.microsoft.com
• CVE record mirror (CVELIST) vulners.com
• OpenCVE entry app.opencve.io
• VulDB entry vuldb.com
• Microsoft Update Catalog search for KB5126651 www.catalog.update.microsoft.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 4 Nov 2026, 08:05.