CVE-2026-83999

Improper link resolution before file access ('link following') in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to elevate privileges locally.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83999	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-09-08 18:21

Updated : 2026-09-11 14:17

NVD link : CVE-2026-83999

Mitre link : CVE-2026-83999

CVE.ORG link : CVE-2026-83999

JSON object : View

Products Affected

microsoft

windows_11_26h1
windows_11_24h2
windows_server_2025
windows_11_25h2

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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