2.18 Disable Mounting of cramfs Filesystems

Information

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 the file /etc/modprobe.d/CIS.conf and add the following line-install cramfs /bin/true

See Also

https://benchmarks.cisecurity.org/tools2/linux/CIS_Ubuntu_12.04_LTS_Server_Benchmark_v1.1.0.pdf