The Cisco router must be configured to produce audit records containing information to establish the source of the events.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-96541	CISC-RT-000220	SV-105679r1_rule		Medium

Description
Without establishing the source of the event, it is impossible to establish, correlate, and investigate the events leading up to an outage or attack. In order to compile an accurate risk assessment and provide forensic analysis, security personnel need to know the source of the event. In addition to logging where events occur within the network, the audit records must also identify sources of events such as IP addresses, processes, and node or device names.

Description

Without establishing the source of the event, it is impossible to establish, correlate, and investigate the events leading up to an outage or attack. In order to compile an accurate risk assessment and provide forensic analysis, security personnel need to know the source of the event. In addition to logging where events occur within the network, the audit records must also identify sources of events such as IP addresses, processes, and node or device names.

STIG	Date
Cisco IOS Router RTR Security Technical Implementation Guide	2019-12-20

Details

Check Text ( C-95377r1_chk )
Review the router configuration to verify that events are logged containing information to establish the source of the events as shown in the example below. ip access-list extended INGRESS_FILTER permit tcp any any established permit tcp host x.11.1.1 eq bgp host x.11.1.2 permit tcp host x.11.1.1 host x.11.1.2 eq bgp permit tcp any host x.11.1.5 eq www permit icmp host x.11.1.1 host x.11.1.2 echo permit icmp any any echo-reply … … … deny ip any any log-input Note: When the log-input parameter is configured on deny statements, the log record will contain the layer 2 address of the forwarding device for any packet being dropped. If the router is not configured to produce audit records containing information to establish the source of the events, this is a finding.

Check Text ( C-95377r1_chk )

Review the router configuration to verify that events are logged containing information to establish the source of the events as shown in the example below.

ip access-list extended INGRESS_FILTER
permit tcp any any established
permit tcp host x.11.1.1 eq bgp host x.11.1.2
permit tcp host x.11.1.1 host x.11.1.2 eq bgp
permit tcp any host x.11.1.5 eq www
permit icmp host x.11.1.1 host x.11.1.2 echo
permit icmp any any echo-reply
…
…
…
deny ip any any log-input

Note: When the log-input parameter is configured on deny statements, the log record will contain the layer 2 address of the forwarding device for any packet being dropped.

If the router is not configured to produce audit records containing information to establish the source of the events, this is a finding.

Fix Text (F-102217r1_fix)
Configure the router to log events containing information to establish where the events occurred as shown in the example below. R5(config)#ip access-list extended INGRESS_FILTER … … … R5(config-ext-nacl)#deny ip any any log-input