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: /etc/modprobe.d/squashfs.conf
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/3148

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-11, CSCv6|3.1, CSCv7|2.6

Plugin: Unix

Control ID: 0bde28a9770aa27a76cedb8c28c8395e86aa59c04c107275620ad21802876f1a