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. Rationale: Removing support for unneeded filesystem types reduces the local attack surface of the server. 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: vim /etc/modprobe.d/cramfs.conf and add the following line: install cramfs /bin/true Run the following command to unload the cramfs module: # rmmod cramfs