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

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-251505	SRG-OS-000378-GPOS-00163	UBTU-20-010461	SV-251505r958820_rule	2025-03-03	2

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.

ℹ️ Check
Verify that Ubuntu operating system disables ability to load the USB storage kernel module. # grep usb-storage /etc/modprobe.d/* \| grep "/bin/false" install usb-storage /bin/false 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.

ℹ️ Check

Verify that Ubuntu operating system disables ability to load the USB storage kernel module. # grep usb-storage /etc/modprobe.d/* | grep "/bin/false" install usb-storage /bin/false 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
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/false >> /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"