Title

Users must be prevented from connecting using Remote Desktop Services. (Cat II impact)

Discussion

Allowing a remote desktop session to a workstation enables another avenue of access that could be exploited. The system must be configured to prevent users from connecting to a computer using Remote Desktop Services.

Check Content

If the following registry value does not exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services\ Value Name: fDenyTSConnections Value Type: REG_DWORD Value: 1 If Remote Desktop Services for remote administration is necessary, enabling this would not be a finding. Restricted Admin mode must be used. This must be document with the ISSO. See Microsoft article KB2871997 for patches required to add this function to systems prior to Windows 8.1. Restricted Admin mode for Remote Desktop Connections can be implemented for each session using a command line switch to start the Remote Desktop Client or through a group policy to enable it for all sessions. The command line to do this is "mstsc /restrictedadmin". To enable this with group policy, configure the policy value for Computer Configuration >> Administrative Templates >> System >> Credentials Delegation >> "Restrict delegation of credentials to remote servers" to "Enabled".

Fix Text

Configure the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Remote Desktop Services >> Remote Desktop Session Host >> Connections "Allow users to connect remotely using Remote Desktop Services" to "Disabled". If Remote Desktop Services for remote administration is necessary, enabling this would not be a finding. Restricted Admin mode must be used. This must be document with the ISSO. See Microsoft article KB2871997 for patches required to add this function to systems prior to Windows 8.1. Restricted Admin mode for Remote Desktop Connections can be implemented for each session using a command line switch to start the Remote Desktop Client or through a group policy to enable it for all sessions. The command line to do this is "mstsc /restrictedadmin". To enable this with group policy, configure the policy value for Computer Configuration >> Administrative Templates >> System >> Credentials Delegation >> "Restrict delegation of credentials to remote servers" to "Enabled".

Additional Identifiers

Rule ID: SV-25259r2_rule

Vulnerability ID: V-14248

Group Title: TS/RDS - Remote User Connections

Expert Comments

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