CVE-2026-66802 - Vulnerability Details - OpenCVE

Concurrent execution using shared resource with improper synchronization ('race condition') in Microsoft Azure Attestation service and Device Health Attestation Service allows an unauthorized attacker to execute code over a network.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Vendors	Products
Microsoft	Windows 10 1809 Windows 11 26h1 Windows Server 2019 Windows Server 2022 Windows Server 2025

No data.

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References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66802

History

Tue, 11 Aug 2026 17:15:00 +0000

Type	Values Removed	Values Added
Description		Concurrent execution using shared resource with improper synchronization ('race condition') in Microsoft Azure Attestation service and Device Health Attestation Service allows an unauthorized attacker to execute code over a network.
Title		Windows Device Health Attestation (DHA) Remote Code Execution Vulnerability
First Time appeared		Microsoft Microsoft windows 10 1809 Microsoft windows 11 26h1 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
Weaknesses		CWE-362 CWE-416
CPEs		cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2019:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 10 1809 Microsoft windows 11 26h1 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66802
Metrics		cvssV3_1 `{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-08-11T17:07:00.979Z

Updated: 2026-08-11T18:52:03.750Z

Reserved: 2026-07-27T19:02:26.600Z

Link: CVE-2026-66802

Vulnrichment

No data.

NVD

Status : Awaiting Analysis

Published: 2026-08-11T17:19:01.587

Modified: 2026-08-11T18:53:42.910

Link: CVE-2026-66802

Redhat

No data.

OpenCVE Enrichment

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