CVE-2026-50668: Windows Resilient File System (ReFS) Elevation of Privilege Vulnerability

Overview

Severity
Medium (CVSS 6.8)
CVSS Vector
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Category
Elevation of Privilege
Exploit Status
Not Exploited
Exploitation Likelihood
Unlikely
Patch Tuesday
2026-Jul
Released
2026-07-14

Description

Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to elevate privileges with a physical attack.

FAQ

According to the CVSS metric, the attack vector is physical (AV:P). What does that mean for this vulnerability? An attacker with physical access to a vulnerable system could insert a specially crafted USB device. Are there additional attack vectors? This vulnerability could also be exploited through a local attack vector. An attacker authenticated as an administrator on a vulnerable system could mount a specially crafted virtual hard drive (VHD) to exploit the system. This scenario results in a lower CVSS score which is why the primary attack vector is listed as Physical in our documentation. What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Affected Products (23)

Windows

  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows 10 Version 21H2 for 32-bit Systems
  • Windows 10 Version 21H2 for ARM64-based Systems
  • Windows 10 Version 21H2 for x64-based Systems
  • Windows Server 2025 (Server Core installation)
  • Windows 11 Version 25H2 for ARM64-based Systems
  • Windows 11 Version 25H2 for x64-based Systems
  • Windows 11 Version 24H2 for ARM64-based Systems
  • Windows 11 Version 24H2 for x64-based Systems
  • Windows Server 2025
  • Windows 11 version 26H1 for x64-based Systems
  • Windows 11 Version 26H1 for ARM64-based Systems
  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)

ESU

  • Windows 10 Version 22H2 for x64-based Systems
  • Windows 10 Version 22H2 for ARM64-based Systems
  • Windows 10 Version 22H2 for 32-bit Systems

Security Updates (7)

Acknowledgments

Thanatos Tian &amp; wgg &amp; @2st__ with Diffract, <a href="https://x.com/_patchpoint_">Donghyeon Oh</a> with <a href="https://patchpoint.io/">Patchpoint</a>, Jonghoi Kim, R4nger with Kunlun Lab &amp; Zhiniang Peng with HUST

Revision History

  • 2026-07-14: Information published.