Title

The operating system must enforce requirements for the connection of mobile devices to operating systems. (Cat II impact)

Discussion

USB storage devices such as thumb drives can be used to introduce unauthorized software and other vulnerabilities. Support for these devices should be disabled and the devices themselves should be tightly controlled.

Check Content

If the system is configured to prevent the loading of the "usb-storage" kernel module, it will contain lines inside any file in "/etc/modprobe.d" or the deprecated"/etc/modprobe.conf". These lines instruct the module loading system to run another program (such as "/bin/true") upon a module "install" event. Run the following command to search for such lines in all files in "/etc/modprobe.d" and the deprecated "/etc/modprobe.conf": $ grep -r usb-storage /etc/modprobe.conf /etc/modprobe.d | grep -i “/bin/true” | grep -v “#” If no line is returned, this is a finding.

Fix Text

To prevent USB storage devices from being used, configure the kernel module loading system to prevent automatic loading of the USB storage driver. To configure the system to prevent the "usb-storage" kernel module from being loaded, add the following line to a file in the directory "/etc/modprobe.d": install usb-storage /bin/true This will prevent the "modprobe" program from loading the "usb-storage" module, but will not prevent an administrator (or another program) from using the "insmod" program to load the module manually.

Additional Identifiers

Rule ID: SV-218087r603264_rule

Vulnerability ID: V-218087

Group Title: SRG-OS-000114

Expert Comments

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