TMA-ROS1-1.1.1.1
Ensure mounting of cramfs filesystems is disabled
Description
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. The audit requires the cramfs module to be unloaded and blocked (modprobe -n -v reports install /bin/true). Host-level control from the CIS ROS Melodic benchmark (Ubuntu 18.04 robot hosts); run as root.
How it is checked
Audit method: Shell command
command -v modprobe >/dev/null 2>&1 || exit 1
grep -qw '^cramfs' /proc/modules 2>/dev/null && { echo 'cramfs is loaded'; exit 1; }
cfg=$(modprobe -n -v cramfs 2>&1)
case "$cfg" in *'install /bin/true'*|*'install /bin/false'*|*'not found'*) echo compliant; exit 0 ;; esac
modprobe --showconfig 2>/dev/null | grep -Eq '^\s*install\s+cramfs\s+/bin/(true|false)' && echo compliant || echo 'cramfs can be loaded'- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Edit or create a file in the /etc/modprobe.d/ directory ending in .conf Example: vi /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
Properties
- Operating systems
- Any
- Tags
- rosros1melodicsystem
- Reference
- CIS ROS Melodic Benchmark v1.0.0 - 1.1.1.1 Ensure mounting of cramfs filesystems is disabled
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target ros