cis-ubuntu1204-v110-9-3-7

name	cis-ubuntu1204-v110-9-3-7
description	Set SSH HostbasedAuthentication to No
category	cis-os-hardening
version	1.1.0
author	cyberstrike-official
tags	["cis","ubuntu",12.04,"linux","authentication","ssh","host-based-auth"]
cis_id	9.3.7
cis_benchmark	CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

9.3.7 Set SSH HostbasedAuthentication to No (Scored)

Profile Applicability

• Level 1

Description

The HostbasedAuthentication parameter specifies if authentication is allowed through trusted hosts via the user of .rhosts, or /etc/hosts.equiv, along with successful public key client host authentication. This option only applies to SSH Protocol Version 2.

Rationale

Even though the .rhosts files are ineffective if support is disabled in /etc/pam.conf, disabling the ability to use .rhosts files in SSH provides an additional layer of protection.

Audit Procedure

Using Command Line

To verify the correct SSH setting, run the following command and verify that the output is as shown:

grep "^HostbasedAuthentication" /etc/ssh/sshd_config

Expected Result

HostbasedAuthentication no

Remediation

Using Command Line

Edit the /etc/ssh/sshd_config file to set the parameter as follows:

HostbasedAuthentication no

Default Value

HostbasedAuthentication no

References

• CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

Profile

Level 1 - Scored