The SSH daemon LoginGraceTime must be set correctly.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-67677	AOSX-11-000722	SV-82167r1_rule		Medium

Description
SSH should be configured to log users out after a 15 minute interval of inactivity and to only wait 30 seconds before timing out login attempts. Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended. In addition, quickly terminating an idle session or an incomplete login attempt will also free up resources committed by the managed network element.

Description

SSH should be configured to log users out after a 15 minute interval of inactivity and to only wait 30 seconds before timing out login attempts. Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended. In addition, quickly terminating an idle session or an incomplete login attempt will also free up resources committed by the managed network element.

STIG	Date
Apple OS X 10.11 Security Technical Implementation Guide	2017-07-11

Details

Check Text ( C-68243r1_chk )
The SSH daemon "LoginGraceTime" must be set correctly. To check the amount of time that a user can login through SSH, run the following command: /usr/bin/sudo /usr/bin/grep ^LoginGraceTime /etc/ssh/sshd_config If the value is not set to "30" or less, this is a finding.

Fix Text (F-73791r1_fix)
In order to make sure that "LoginGraceTime" is configured correctly, run the following command: /usr/bin/sudo /usr/bin/sed -i.bak 's/.LoginGraceTime./LoginGraceTime 30/' /etc/ssh/sshd_config