The Cisco ASA must be configured to terminate all network connections associated with a device management session at the end of the session, or the session must be terminated after five minutes of inactivity except to fulfill documented and validated mission requirements.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-239920	CASA-ND-000690	SV-239920r916342_rule		High

Description
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 will also free up resources committed by the managed network element. Terminating network connections associated with communications sessions includes, for example, de-allocating associated TCP/IP address/port pairs at the operating system level, or de-allocating networking assignments at the application level if multiple application sessions are using a single, operating system-level network connection. This does not mean that the device terminates all sessions or network access; it only ends the inactive session and releases the resources associated with that session.

Description

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 will also free up resources committed by the managed network element. Terminating network connections associated with communications sessions includes, for example, de-allocating associated TCP/IP address/port pairs at the operating system level, or de-allocating networking assignments at the application level if multiple application sessions are using a single, operating system-level network connection. This does not mean that the device terminates all sessions or network access; it only ends the inactive session and releases the resources associated with that session.

STIG	Date
Cisco ASA NDM Security Technical Implementation Guide	2023-09-13

Details

Check Text ( C-43153r916163_chk )
Review the Cisco ASA configuration to verify all network connections associated with a device management have an idle timeout value set to five minutes or less as shown in the following example: http server idle-timeout 5 … … … ssh timeout 5 … … … console timeout 5 If the Cisco ASA is not configured to terminate all network connections associated with a device management after five minutes of inactivity, this is a finding.

Check Text ( C-43153r916163_chk )

Review the Cisco ASA configuration to verify all network connections associated with a device management have an idle timeout value set to five minutes or less as shown in the following example:

http server idle-timeout 5
…
…
…
ssh timeout 5
…
…
…
console timeout 5

If the Cisco ASA is not configured to terminate all network connections associated with a device management after five minutes of inactivity, this is a finding.

Fix Text (F-43112r916164_fix)
Set the idle timeout value to five minutes or less for console, ssh, and http (if ASDM is used) access. SW1(config)# ssh timeout 5 SW1(config)# console timeout 5 ASA(config)# http server idle-timeout 5 SW1(config)# end