CIS Microsoft Windows 10 Enterprise Release 1909 Benchmark

2.3.15 Systemobjects

This section contains recommendations related to system objects.

2.3.15.1 (L1) Ensure 'Systemobjects: Require case insensitivity for non- Windows subsystems' is set to 'Enabled' (Scored)

ProfileApplicability:

 Level 1 (L1) - Corporate/Enterprise Environment (general use)

Description:

This policy setting determines whether case insensitivity is enforced for all subsystems. The Microsoft Win32 subsystem is case insensitive. However, the kernel supports case sensitivity for other subsystems, such as the Portable Operating System Interface for UNIX (POSIX). Because Windows is case insensitive (but the POSIX subsystem will support case sensitivity), failure to enforce this policy setting makes it possible for a user of the POSIX subsystem to create a file with the same name as another file by using mixed case to label it. Such a situation can block access to these files by another user who uses typical Win32 tools, because only one of the files will be available.

The recommended state for this setting is: Enabled .

Rationale:

Because Windows is case-insensitive but the POSIX subsystem will support case sensitivity, failure to enable this policy setting would make it possible for a user of that subsystem to create a file with the same name as another file but with a different mix of upper and lower case letters. Such a situation could potentially confuse users when they try to access such files fromnormal Win32 tools because only one of the files will be available.

Audit:

Navigate to the UI Path articulated in the Remediation section and confirm it is set as prescribed. This group policy setting is backed by the following registry location:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Kernel:ObCaseInsensitive

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