Vulnerability in Microsoft Windows 11 Version 24h2

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 metric

CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-83999?
CVE-2026-83999 is a high-severity vulnerability in Microsoft Windows 11 Version 24h2, classified under Improper Link Resolution Before File Access. CVSS score: 7.0/10. Published 2026-09-08.
How severe is CVE-2026-83999?
High severity. CVSS v3 base score is 7.0 out of 10.