CVE-2026-50381: Composite Image File System driver (cimfs.sys) Information Disclosure Vulnerability

Overview

Severity

Medium (CVSS 5.5)

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Category

Information Disclosure

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Jul

Released

2026-07-14

Description

Access of resource using incompatible type ('type confusion') in Composite Image File System Driver allows an authorized attacker to disclose information locally.

FAQ

What type of information could be disclosed by this vulnerability? The type of information that could be disclosed if an attacker successfully exploited this vulnerability is file metadata.

Affected Products (15)

Windows

• 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

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 (6)

• 5099540
• 5099539
• 5099536
• 5101650
• 5095051
• 5101649

Acknowledgments

<a href="https://www.linkedin.com/in/jung-hyun-yoon-bb9988114/">YuilMuil(Yoon Jung Hyun)</a>

Revision History

• 2026-07-14: Information published.