The Ubuntu operating system must disable automatic mounting of Universal Serial Bus (USB) mass storage driver.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-219339	UBTU-18-010509	SV-219339r853398_rule		Medium

Description
Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. Peripherals include, but are not limited to, such devices as flash drives, external storage, and printers.

STIG	Date
Canonical Ubuntu 18.04 LTS Security Technical Implementation Guide	2023-09-08

Details

Check Text ( C-21064r802370_chk )
Note: The "install" and "blacklist" methods are utilized together to fully disable automatic mounting of the USB mass storage driver. Verify that Ubuntu operating system disables ability to load the USB storage kernel module: $ grep usb-storage /etc/modprobe.d/* \| grep "/bin/true" install usb-storage /bin/true If the command does not return any output, or the line is commented out, this is a finding. Verify the operating system disables the ability to use USB mass storage device: $ grep usb-storage /etc/modprobe.d/* \| grep -i "blacklist" blacklist usb-storage If the command does not return any output, or the line is commented out, this is a finding.

Check Text ( C-21064r802370_chk )

Note: The "install" and "blacklist" methods are utilized together to fully disable automatic mounting of the USB mass storage driver.

Verify that Ubuntu operating system disables ability to load the USB storage kernel module:
$ grep usb-storage /etc/modprobe.d/* | grep "/bin/true"

install usb-storage /bin/true

If the command does not return any output, or the line is commented out, this is a finding.

Verify the operating system disables the ability to use USB mass storage device:
$ grep usb-storage /etc/modprobe.d/* | grep -i "blacklist"

blacklist usb-storage

If the command does not return any output, or the line is commented out, this is a finding.

Fix Text (F-21063r802371_fix)
Configure the Ubuntu operating system to disable using the USB storage kernel module. Create a file under "/etc/modprobe.d" to contain the following: $ sudo su -c "echo install usb-storage /bin/true >> /etc/modprobe.d/DISASTIG.conf" Configure the operating system to disable the ability to use USB mass storage devices: $ sudo su -c "echo blacklist usb-storage >> /etc/modprobe.d/DISASTIG.conf"