Use After Free in Microsoft Windows 10 1809
CVE-2026-66802
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Device Health Attestation (DHA) allows an unauthorized attacker to execute code over a network.
Vulnerability class: Race Condition
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (43.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.002
Affected products
- Microsoft Windows 10 1809
- Microsoft Windows 10 Version 1809 — versions 10.0.17763.0
- Microsoft Windows 11 26h1
- Microsoft Windows 11 Version 26h1 — versions 10.0.28000.0
- Microsoft Windows Server 2019 — versions 10.0.17763.0
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core Installation) — versions 10.0.17763.0
- Microsoft Windows Server 2022 — versions 10.0.20348.0
- Microsoft Windows Server 2022
- Microsoft Windows Server 2025 — versions 10.0.26100.0
Weakness classification (CWE)
References
- Windows Device Health Attestation (DHA) Remote Code Execution Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-66802?
- CVE-2026-66802 is a high-severity vulnerability in Microsoft Windows 10 1809, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2026-08-11.
- How severe is CVE-2026-66802?
- High severity. CVSS v3 base score is 8.1 out of 10.