CVE-2026-50458: 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

Less Likely

Patch Tuesday

2026-Jul

Released

2026-07-14

Last Updated

2026-07-22

EPSS Score

0.26% (percentile: 16.9%)

Description

Use after free in Microsoft 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 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

Security Updates (3)

• 5099536
• 5101650
• 5101649

Acknowledgments

anonymous, anonymous, <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/rotcee_">Rotce</a>

Revision History

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