Name: Microsoft Windows: CVE-2026-83586: Windows Resilient File System (ReFS) Deduplication Service Elevation of Privilege Vulnerability
Creator: Rapid7
Published: 2026-10-13T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-83586, CWE-1390, CVSS 7.8, EPSS 0.00284

Weak authentication in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to elevate privileges locally.

CVSS Details

CVSS 3.1 Base Score: 7.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Microsoft Windows	—	2026-10 Cumulative Update for Microsoft Windows 11, version 23H2 (KB5126653)2026-10 Cumulative Update for Microsoft Windows 11, version 24H2 (KB5127648)2026-10 Cumulative Update for Microsoft Windows 11, version 25H2 (KB5127648)2026-10 Cumulative Update for Microsoft Windows 11, version 26H1 (KB5127646)2026-10 Cumulative Update for Microsoft Windows Server 2025, version 24H2 (KB5126646)	Oct 13, 2026	Oct 13, 2026

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CVSS Details

Covered by Rapid7

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