Users must be prevented from mapping local COM ports and redirecting data from the Remote Desktop Session Host to local COM ports. (Remote Desktop Services Role).

From Windows Server 2012/2012 R2 Member Server Security Technical Implementation Guide

Associated with IA controls: ECSC-1

Associated with: CCI-002314

SV-52224r2_rule Users must be prevented from mapping local COM ports and redirecting data from the Remote Desktop Session Host to local COM ports. (Remote Desktop Services Role).

Vulnerability discussion

Preventing the redirection of Remote Desktop session data to a client computer's COM ports helps reduce possible exposure of sensitive data.

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: fDisableCcm Type: REG_DWORD Value: 1

Fix text

Configure the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Remote Desktop Services -> Remote Desktop Session Host -> Device and Resource Redirection -> "Do not allow COM port redirection" to "Enabled".

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