CVE-2026-50466: Microsoft Brokering File System Elevation of Privilege Vulnerability

Overview

Severity
High (CVSS 7.8)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/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
Last Updated
2026-08-21
EPSS Score
0.33% (percentile: 25.8%)

Description

Use after free in Windows Brokering File System allows an authorized attacker to elevate privileges locally.

Affected Products (8)

Windows

  • 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 x64-based Systems
  • Windows 11 Version 24H2 for ARM64-based Systems
  • Windows Server 2025
  • Windows 11 version 26H1 for x64-based Systems
  • Windows 11 Version 26H1 for ARM64-based Systems

Security Updates (3)

Acknowledgments

byzero with Kunlun Lab & Zhiniang Peng (HUST), <a href="https://www.linkedin.com/in/p1nkjelly/">Minwoo Jeong (P1nkjelly)</a> with <a href="https://hacking.kaist.ac.kr/">KAIST Hacking Lab</a>, <a href="https://x.com/bad_jubies">Grant Hume</a>, Anonymous

Revision History

  • 2026-07-14: Information published.
  • 2026-07-22: Updated an acknowledgement. This is an informational change only.
  • 2026-08-21: Updated an acknowledgement. This is an informational change only.