cis-ubuntu-14-04-lts-3-4-2-ensure-etc-hosts-allow-is-configured

name	CIS Ubuntu 14.04 LTS - 3.4.2 Ensure /etc/hosts.allow is configured
description	Verify that /etc/hosts.allow is configured to permit authorized network access
category	cis-os-hardening
version	2.1.0
author	cyberstrike-official
tags	["cis","ubuntu","ubuntu-14.04","level-1","scored","tcp-wrappers","network"]
cis_id	3.4.2
cis_benchmark	CIS Ubuntu Linux 14.04 LTS Benchmark v2.1.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	medium

3.4.2 Ensure /etc/hosts.allow is configured (Scored)

Profile Applicability

• Level 1 - Server
• Level 1 - Workstation

Description

The /etc/hosts.allow file specifies which IP addresses are permitted to connect to the host. It is intended to be used in conjunction with the /etc/hosts.deny file.

Rationale

The /etc/hosts.allow file supports access control by IP and helps ensure that only authorized systems can connect to the system.

Audit Procedure

Run the following command and verify the contents of the /etc/hosts.allow file:

cat /etc/hosts.allow

Expected Result

The file should contain appropriate network allow rules for your environment.

Remediation

Run the following command to create /etc/hosts.allow:

echo "ALL: <net>/<mask>, <net>/<mask>, ..." >/etc/hosts.allow

where each <net>/<mask> combination (for example, "192.168.1.0/255.255.255.0") represents one network block in use by your organization that requires access to this system.

Default Value

Contents of /etc/hosts.allow file will vary depending on your network configuration.

References

• CIS Controls: 9.2 - Leverage Host-based Firewalls

Profile

• Level 1 - Server
• Level 1 - Workstation