TMA-ROS1-2.2.8

Ensure DNS Server is not enabled

MediumLevel 1Automatedros

Description

The Domain Name System (DNS) is a hierarchical naming system that maps names to IP addresses for computers, services and other resources connected to a network. The audit requires the DNS server unit(s) bind9 not to be enabled or active (systemctl). 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

shell

command -v systemctl >/dev/null 2>&1 || exit 1
bad=0
for u in bind9; do
  s=$(systemctl is-enabled "$u" 2>/dev/null)
  case "$s" in enabled|enabled-runtime|alias|indirect) echo "$u is $s"; bad=1 ;; esac
  systemctl is-active --quiet "$u" 2>/dev/null && { echo "$u is active"; bad=1; }
done
[ "$bad" -eq 0 ] && echo compliant

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Run the following commands to disable DNS server: # systemctl --now disable bind9

Properties

Operating systems: Any
Tags: rosros1melodicservices
Reference: CIS ROS Melodic Benchmark v1.0.0 - 2.2.8 Ensure DNS Server is not enabled

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target ros