Title

Terminal Services – Prevent COM Port Redirection (Terminal Server Role). (Cat II impact)

Discussion

This check verifies that the system is configured to prevent users from mapping local COM ports and redirecting data from the Terminal Server to local COM ports.

Check Content

If the following registry value doesn’t exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Subkey: \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 -> Terminal Services -> Terminal Server -> Device and Resource Redirection “Do not allow COM port redirection” to “Enabled”.

Additional Identifiers

Rule ID: SV-16941r1_rule

Vulnerability ID: V-15997

Group Title: TS/RDS – COM Port Redirection

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.