Table of Contents

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

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

# cat /etc/hosts.allow

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.

Notes

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