CVE-2026-83999
Windows Resilient File System (ReFS) Deduplication Service Elevation of Privilege Vulnerability
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 10.0.26100.9445, 10.0.26200.9445, 10.0.28000.2954, 10.0.26100.33438
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
Improper link resolution before file access ('link following') in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to elevate privileges locally.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Microsoft Windows 11 Version 24H2
From 10.0.26100.0 · fixed in 10.0.26100.9445
- Microsoft Windows 11 Version 25H2
From 10.0.26200.0 · fixed in 10.0.26200.9445
- Microsoft Windows 11 version 26H1
From 10.0.28000.0 · fixed in 10.0.28000.2954
- Microsoft Windows Server 2025
From 10.0.26100.0 · fixed in 10.0.26100.33438
- Microsoft Windows Server 2025 (Server Core installation)
From 10.0.26100.0 · fixed in 10.0.26100.33438