1.1.1.6 Ensure mounting of squashfs filesystems is disabled (Scored)

Level 1 - Server 
Level 1 - Workstation

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.

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

Run the following commands and verify the output is as indicated:

# modprobe -n -v squashfs 
install /bin/true 
# lsmod | grep squashfs
<No output>

Edit or create the file /etc/modprobe.d/CIS.conf and add the following line:

install squashfs /bin/true
  • ubuntu1604/1/1/1/6.txt
  • Last modified: 2017/05/02 14:01
  • by Piotr Kłoczewski