Anonymous enumeration of SAM accounts will not be allowed.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-26283	3.019	SV-33732r1_rule	ECSC-1	High

Description
This is a Category 1 finding as it allows anonymous logon users (null session connections) to list all account names, thus providing a list of potential points to attack the system.

STIG	Date
Windows Server 2008 R2 Member Server Security Technical Implementation Guide	2013-03-14

Details

Check Text ( C-33725r1_chk )
Analyze the system using the Security Configuration and Analysis snap-in. Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. If the value for “Network access: Do not allow anonymous enumeration of SAM accounts” is not set to “Enabled”, then this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Control\Lsa\ Value Name: RestrictAnonymousSAM Value Type: REG_DWORD Value: 1

Check Text ( C-33725r1_chk )

Analyze the system using the Security Configuration and Analysis snap-in.
Expand the Security Configuration and Analysis tree view.
Navigate to Local Policies -> Security Options.

If the value for “Network access: Do not allow anonymous enumeration of SAM accounts” is not set to “Enabled”, then this is a finding.

The policy referenced configures the following registry value:

Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \System\CurrentControlSet\Control\Lsa\

Value Name: RestrictAnonymousSAM

Value Type: REG_DWORD
Value: 1

Fix Text (F-29359r1_fix)
Configure the policy values for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> “Network access: Do not allow anonymous enumeration of SAM accounts” to “Enabled".