1.1.1.6 Ensure mounting of squashfs filesystems is disabled (Scored)
Profile Applicability
Level 1 - Server Level 1 - Workstation
Description
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 server. If this filesystem type is not needed, disable it.
Audit
Run the following commands and verify the output is as indicated:
# modprobe -n -v squashfs install /bin/true # lsmod | grep squashfs <No output>
Remediation
Edit or create the file /etc/modprobe.d/CIS.conf
and add the following line:
install squashfs /bin/true