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

Summary

Impact: Information Disclosure. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

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.

Security updates
10.0.20348.5386 — https://support.microsoft.com/help/5099540
10.0.19044.7548 — https://support.microsoft.com/help/5099539
10.0.26100.33158 — https://support.microsoft.com/help/5099536
10.0.26200.8875 — https://support.microsoft.com/help/5101650
10.0.28000.2525 — https://support.microsoft.com/help/5101649

Vulnerabilities 1

Medium 5.5

CVE-2026-50381

Composite Image File System driver (cimfs.sys) Information Disclosure Vulnerability

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

Microsoft Windows Server 2022 Windows 10 Version 21H2 Windows 10 Version 22H2 Windows

Jul 14, 2026

Revision history

2026-07-14 #1
Information published.

References

CVE-2026-50381 Composite Image File System driver (cimfs.sys) Information Disclosure Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50381
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss