1.1.1.2.1.39 Set 'MSS: (SafeDllSearchMode) Enable Safe DLL search mode(recommended)' to 'Enabled'

Information

The registry value entry SafeDllSearchMode was added to the template file in the HKEY_LOCAL_MACHINE\ SYSTEM\CurrentControlSet\Control\Session Manager\ registry key. The entry appears as MSS: (SafeDllSearchMode) Enable Safe DLL search mode (recommended) in the SCE. The DLL search order can be configured to search for DLLs that are requested by running processes in one of two ways: . Search folders specified in the system path first, and then search the current working folder. . Search current working folder first, and then search the folders specified in the system path. When enabled, the registry value is set to 1. With a setting of 1, the system first searches the folders that are specified in the system path and then searches the current working folder. When disabled the registry value is set to 0 and the system first searches the current working folder and then searches the folders that are specified in the system path. If a user unknowingly executes hostile code that was packaged with additional files that include modified versions of system DLLs, the hostile code could load its own versions of those DLLs and potentially increase the type and degree of damage the code can render.

Solution

To implement the recommended configuration state, set the following Group Policy setting to 1.

Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\MSS- (SafeDllSearchMode) Enable Safe DLL search mode (recommended)

Impact- Applications will be forced to search for DLLs in the system path first. For applications that require unique versions of these DLLs that are included with the application, this entry could cause performance or stability problems.

See Also

https://workbench.cisecurity.org/files/42

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6, CCE|CCE-3778-8, CSCv6|3.1

Plugin: Windows

Control ID: 46817cc9cb5b9a021428ce87c2cded9b33c2c8fd3d3c8adcb06b9468923f2127