The cramfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems. A cramfs 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.
Edit or create the file /etc/modprobe.d/CIS.conf and add the following line: install cramfs /bin/true Run the following command to unload the cramfs module: # rmmod cramfs