Type Confusion in Microsoft Windows and Windows Server - CVE-2026-50381
Published: July 17, 2026
Vulnerability identifier: #VU137991
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-50381
CWE-ID: CWE-843
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to type confusion in Composite Image File System Driver (cimfs.sys) when accessing a resource using an incompatible type. A local user can trigger the flaw to disclose sensitive information.
The disclosed information is limited to file metadata.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-50381
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7548, 10 22H2 10.0.19045.7548, 11 24H2 10.0.26100.8875, 11 25H2 10.0.26200.8875, 11 26H1 10.0.28000.2269, 11 26H1 10.0.28000.2525
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2022 10.0.20348.5386, 2025 10.0.26100.33158
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2022 10.0.20348.5386, 2025 10.0.26100.33158