RHEL 9 must have the USBGuard package installed.

The USBguard-daemon is the main component of the USBGuard software framework. It runs as a service in the background and enforces the USB device authorization policy for all USB devices. The policy is defined by a set of rules using a rule language described in the usbguard-rules.conf file. The policy and the authorization state of USB devices can be modified during runtime using the usbguard tool.

The system administrator (SA) must work with the site information system security officer (ISSO) to determine a list of authorized peripherals and establish rules within the USBGuard software framework to allow only authorized devices.

Verify USBGuard is installed on the operating system with the following command:

$ sudo dnf list installed usbguard

Example output:

Installed Packages usbguard.x86_64 1.0.0-10.el9_1.2 @rhel-9-for-x86_64-appstream-rpms

If the USBGuard package is not installed, ask the SA to indicate how unauthorized peripherals are being blocked.

If there is no evidence that unauthorized peripherals are being blocked before establishing a connection, this is a finding.

If the system is virtual machine with no virtual or physical USB peripherals attached, this is not a finding.

Install the usbguard package with the following command:

$ sudo dnf install usbguard

Enable the service to start on boot and then start it with the following commands: $ sudo systemctl enable usbguard $ sudo systemctl start usbguard

Verify the status of the service with the following command: $ sudo systemctl status usbguard

Note: usbguard will need to be configured to allow authorized devices once it is enabled on RHEL 9.