1.1.1.5 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: vi /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/2658

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6, CSCv6|3.1, CSCv7|5.1

Plugin: Unix

Control ID: 7c312b1328300bea74a851bbec49c6d9357e6cc924563cc4d2350dcf80d1f0a4