CVE-2026-83999
highImproper link resolution before file access ('link following') in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to e…
Vendor / product: Microsoft — windows 11 24h2
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
7.0
7.0 (CVSS v3.1)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Severity source: NVD CVSS v3.1 (secure@microsoft.com)
Timeline (UTC)
Published: 2026-09-08 18:21
Modified: 2026-09-11 14:17
NVD status: Analyzed
Last synced 1 day ago
Verified against the source API 2026-10-27 06:52 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
microsoft / windows_11_24h2 <10.0.26100.9445
microsoft / windows_11_25h2 <10.0.26200.9445
microsoft / windows_11_26h1 <10.0.28000.2954
microsoft / windows_server_2025 <10.0.26100.33438
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83999
Patch / mitigation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83999
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83999 secure@microsoft.com
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:52 UTC · record ↗