cis-ubuntu2004-v300-2-1-5

name	cis-ubuntu2004-v300-2-1-5
description	Ensure dnsmasq services are not in use
category	cis-networking
version	3.0.0
author	cyberstrike-official
tags	["cis","ubuntu","linux","ubuntu-20.04","services"]
cis_id	2.1.5
cis_benchmark	CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

2.1.5 Ensure dnsmasq services are not in use (Automated)

Profile

• Level 1 - Server
• Level 1 - Workstation

Description

dnsmasq is a lightweight tool that provides DNS caching, DNS forwarding, and DHCP (Dynamic Host Configuration Protocol) services.

Rationale

Unless a system is specifically designated to act as a DNS caching proxy or DHCP server, it is recommended that the service be disabled to reduce the potential attack surface.

Audit Procedure

Command Line

Run the following command to verify dnsmasq is not installed:

# dpkg-query -W -f='${binary:Package}\t${Status}\t${db:Status-Status}\n' dnsmasq

If installed, run:

# systemctl is-enabled dnsmasq.service
# systemctl is-active dnsmasq.service

Verify the service is not enabled and not active.

Expected Result

dnsmasq should not be installed, or if installed, the service should be stopped and masked.

Remediation

Command Line

Run the following commands to stop, mask, and purge dnsmasq:

# systemctl stop dnsmasq.service
# systemctl mask dnsmasq.service
# apt purge dnsmasq

Default Value

dnsmasq is not installed by default.

References

1. NIST SP 800-53 Rev. 5: CM-7

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software		x	x
v7	9.2 Ensure Only Approved Ports, Protocols and Services Are Running		x	x

MITRE ATT&CK Mappings: T1203, T1210, T1543, T1543.002 | TA0008 | M1042