The system must be configured to use Safe DLL Search Mode.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-3479	WN08-SO-000045	SV-48117r1_rule		Medium

Description
The default search behavior, when an application calls a function in a Dynamic Link Library (DLL), is to search the current directory, followed by the directories contained in the system's path environment variable. An unauthorized DLL, inserted into an application's working directory, could allow malicious code to be run on the system. Setting this policy value forces the system to search the %Systemroot% for the DLL before searching the current directory or the rest of the path.

Description

The default search behavior, when an application calls a function in a Dynamic Link Library (DLL), is to search the current directory, followed by the directories contained in the system's path environment variable. An unauthorized DLL, inserted into an application's working directory, could allow malicious code to be run on the system. Setting this policy value forces the system to search the %Systemroot% for the DLL before searching the current directory or the rest of the path.

STIG	Date
Windows 8/8.1 Security Technical Implementation Guide	2017-02-27

Details

Check Text ( C-44843r1_chk )
Analyze the system using the Security Configuration and Analysis snap-in. (See "Performing Analysis with the Security Configuration and Analysis Snap-in" in the STIG Overview document.) Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. (See "Updating the Windows Security Options File" in the STIG Overview document if MSS settings are not visible in the system's policy tools.) If the value for "MSS: (SafeDllSearchMode) Enable Safe DLL search mode (recommended)" is not set to "Enabled", this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Control\Session Manager\ Value Name: SafeDllSearchMode Value Type: REG_DWORD Value: 1

Check Text ( C-44843r1_chk )

Analyze the system using the Security Configuration and Analysis snap-in. (See "Performing Analysis with the Security Configuration and Analysis Snap-in" in the STIG Overview document.)
Expand the Security Configuration and Analysis tree view.
Navigate to Local Policies -> Security Options.

(See "Updating the Windows Security Options File" in the STIG Overview document if MSS settings are not visible in the system's policy tools.)

If the value for "MSS: (SafeDllSearchMode) Enable Safe DLL search mode (recommended)" is not set to "Enabled", this is a finding.

The policy referenced configures the following registry value:

Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \System\CurrentControlSet\Control\Session Manager\

Value Name: SafeDllSearchMode

Value Type: REG_DWORD
Value: 1

Fix Text (F-41254r1_fix)
Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> "MSS: (SafeDllSearchMode) Enable Safe DLL search mode (recommended)" to "Enabled".