Information
This policy setting allows you to specify a list of Plug and Play hardware IDs and compatible IDs for devices that Windows is prevented from installing. This policy setting takes precedence over any other policy setting that allows Windows to install a device.
If you enable this policy setting, Windows is prevented from installing a device whose hardware ID or compatible ID appears in the list you create. If you enable this policy setting on a remote desktop server, the policy setting affects redirection of the specified devices from a remote desktop client to the remote desktop server.
If you disable or do not configure this policy setting, devices can be installed and updated as allowed or prevented by other policy settings.
The recommended state for this setting is: PCI\CC_0C0A
Note: This device ID is for Thunderbolt controllers. The USB Type-C (USB-C) port standard that is now common in many computers, especially laptops, utilizes Thunderbolt technology, and therefore may be affected by this restriction. If your organization needs to use USB-C extensively, you may need to decide, internally, to allow yourselves an exception to this recommendation. However, please ensure that all necessary decision-makers have accepted the increased risk of BitLocker encryption key theft (and therefore data theft) via malicious Thunderbolt devices (when left unattended), by doing so.
Note #2: In versions of Windows 10 Release 1803 (and newer), there is a new control named Enumeration policy for external devices incompatible with Kernel DMA Protection available that mitigates much of the risk for malicious devices that may perform Direct Memory Access (DMA) attacks. The newer control is also now part of the Windows 10 CIS benchmark, in section 18.8.26. However, if your environment still contains any Windows 10 Release 1709 (or older) workstations, then the newer control will not work, so this setting remains important to disable Thunderbolt devices on those systems.
Rationale:
A BitLocker-protected computer may be vulnerable to Direct Memory Access (DMA) attacks when the computer is turned on or is in the Standby power state - this includes when the workstation is locked.
BitLocker with TPM-only authentication lets a computer enter the power-on state without any pre-boot authentication. Therefore, an attacker may be able to perform DMA attacks.
This issue is documented in Microsoft Knowledge Base article 2516445: Blocking the SBP-2 driver and Thunderbolt controllers to reduce 1394 DMA and Thunderbolt DMA threats to BitLocker.
Solution
To establish the recommended configuration via GP, set the following UI path to Enabled, and add PCI\CC_0C0A to the Device IDs list:
Computer Configuration\Policies\Administrative Templates\System\Device Installation\Device Installation Restrictions\Prevent installation of devices that match any of these device IDs
Note: This Group Policy path is provided by the Group Policy template DeviceInstallation.admx/adml that is included with all versions of the Microsoft Windows Administrative Templates.
Impact:
Thunderbolt controllers will be prevented from being installed in Windows.
Default Value:
None. (No device ID types are prevented from installation.)
References:
1. CCE-35360-7
Notes:
Documented in MSKB 2516445.