1.1.1.6 Ensure mounting of squashfs filesystems is disabled - modprobe

Information

The squashfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems (similar to cramfs ). A squashfs image can be used without having to first decompress the image.

Rationale:

Removing support for unneeded filesystem types reduces the local attack surface of the system. If this filesystem type is not needed, disable it.

Solution

Edit or create a file in the /etc/modprobe.d/ directory ending in .conf
Example: vim /etc/modprobe.d/squashfs.conf
and add the following line:

install squashfs /bin/true

Run the following command to unload the squashfs module:

# rmmod squashfs

See Also

https://workbench.cisecurity.org/files/3399

Item Details

Category: CONFIGURATION MANAGEMENT, SYSTEM AND SERVICES ACQUISITION

References: 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|CM-7(1), 800-53|CM-9, 800-53|SA-3, 800-53|SA-8, 800-53|SA-10, CSCv7|13

Plugin: Unix

Control ID: b87bd2843baba13f1ec377937622681ed7dbe15dc3e07bb08e0c1dde93e79816