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 the file /etc/modprobe.d/CIS.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/3738

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-7b.

Plugin: Unix

Control ID: 2da072d48671d181259149af4eeb338a53d3545a83d2e809fbb83bf7be038df4