cis-ubuntu1604-v200-3-5-2-1

name	cis-ubuntu1604-v200-3-5-2-1
description	Ensure nftables is installed
category	cis-networking
version	2.0.0
author	cyberstrike-official
tags	["cis","ubuntu","linux","ubuntu-16.04","firewall"]
cis_id	3.5.2.1
cis_benchmark	CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 3.5.2.1

Profile

• Level: Level 1 - Server, Level 1 - Workstation
• Assessment Status: Automated

Description

nftables provides a new in-kernel packet classification framework that is based on a network-specific Virtual Machine (VM) and a new nft userspace command line tool. nftables reuses the existing Netfilter subsystems such as the existing hook infrastructure, the connection tracking system, NAT, userspace queuing and logging subsystem.

Notes:

• nftables is available in Linux kernel 3.13 and newer.
• Only one firewall utility should be installed and configured.
• Changing firewall settings while connected over the network can result in being locked out of the system.

Rationale

nftables is a subsystem of the Linux kernel that can protect against threats originating from within a corporate network to include malicious mobile code and poorly configured software on a host.

Audit Procedure

Command Line

Run the following command to verify that nftables is installed:

dpkg-query -s nftables | grep 'Status: install ok installed'

Expected Result

Status: install ok installed

Remediation

Command Line

Run the following command to install nftables:

apt install nftables

References

None

CIS Controls

Version 7

9.4 Apply Host-based Firewalls or Port Filtering - Apply host-based firewalls or port filtering tools on end systems, with a default-deny rule that drops all traffic except those services and ports that are explicitly allowed.