1.1.1.1 Ensure mounting of cramfs filesystems is disabled

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.

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

Solution

Edit or create a file in the /etc/modprobe.d/ directory ending inconf with a line that reads install cramfs /bin/false and a line the reads blacklist cramfs

Example:

# printf "install cramfs /bin/false
blacklist cramfs
" >> /etc/modprobe.d/cramfs.conf

Run the following command to unload the cramfs module:

# modprobe -r cramfs

See Also

https://workbench.cisecurity.org/files/3796

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6, 800-53|CM-7, CSCv7|9.2

Plugin: Unix

Control ID: 470944bd1c86c40ff20aee1ac3021385447386f9ea19a5115521fc51098361e2