The Cisco router must be configured to use keys with a duration not exceeding 180 days for authenticating routing protocol messages.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-96507	CISC-RT-000030	SV-105645r1_rule		Medium

Description
If the keys used for routing protocol authentication are guessed, the malicious user could create havoc within the network by advertising incorrect routes and redirecting traffic. Some routing protocols allow the use of key chains for authentication. A key chain is a set of keys that is used in succession, with each having a lifetime of no more than 180 days. Changing the keys frequently reduces the risk of them eventually being guessed. Keys cannot be used during time periods for which they are not activated. If a time period occurs during which no key is activated, neighbor authentication cannot occur, and therefore routing updates will fail. Therefore, ensure that for a given key chain, key activation times overlap to avoid any period of time during which no key is activated.

Description

If the keys used for routing protocol authentication are guessed, the malicious user could create havoc within the network by advertising incorrect routes and redirecting traffic. Some routing protocols allow the use of key chains for authentication. A key chain is a set of keys that is used in succession, with each having a lifetime of no more than 180 days. Changing the keys frequently reduces the risk of them eventually being guessed. Keys cannot be used during time periods for which they are not activated. If a time period occurs during which no key is activated, neighbor authentication cannot occur, and therefore routing updates will fail. Therefore, ensure that for a given key chain, key activation times overlap to avoid any period of time during which no key is activated.

STIG	Date
Cisco IOS Router RTR Security Technical Implementation Guide	2019-07-25

Details

Check Text ( C-95343r1_chk )
This requirement is not applicable for the DODIN Backbone. Review the start times for each key within the configured key chains used for routing protocol authentication as shown in the example below. key chain OSPF_KEY_CHAIN key 1 key-string xxxxxxx send-lifetime 00:00:00 Jan 1 2018 23:59:59 Mar 31 2018 accept-lifetime 00:00:00 Jan 1 2018 01:05:00 Apr 1 2018 key 2 key-string yyyyyyy send-lifetime 00:00:00 Apr 1 2018 23:59:59 Jun 30 2018 accept-lifetime 23:55:00 Mar 31 2018 01:05:00 Jul 1 2018 Note: Key chains must be configured to authenticate routing protocol messages as it is the only way to set an expiration. If any key has a lifetime of more than 180 days, this is a finding.

Check Text ( C-95343r1_chk )

This requirement is not applicable for the DODIN Backbone.

Review the start times for each key within the configured key chains used for routing protocol authentication as shown in the example below.

key chain OSPF_KEY_CHAIN
key 1
key-string xxxxxxx
send-lifetime 00:00:00 Jan 1 2018 23:59:59 Mar 31 2018
accept-lifetime 00:00:00 Jan 1 2018 01:05:00 Apr 1 2018
key 2
key-string yyyyyyy
send-lifetime 00:00:00 Apr 1 2018 23:59:59 Jun 30 2018
accept-lifetime 23:55:00 Mar 31 2018 01:05:00 Jul 1 2018

Note: Key chains must be configured to authenticate routing protocol messages as it is the only way to set an expiration.

If any key has a lifetime of more than 180 days, this is a finding.

Fix Text (F-102183r1_fix)
This requirement is not applicable for the DODIN Backbone. Configure each key used for routing protocol authentication to have a lifetime of no more than 180 days as shown in the example below. R5(config)#key chain OSPF_KEY_CHAIN R5(config-keychain)#key 1 R5(config-keychain-key)#key-string xxxxxx R5(config-keychain-key)#send-lifetime 00:00:00 Jan 1 2018 23:59:59 Mar 31 2018 R5(config-keychain-key)#accept-lifetime 00:00:00 Jan 1 2018 01:05:00 Apr 1 2018 R5(config-keychain-key)#exit R5(config-keychain)#key 2 R5(config-keychain-key)#key-string yyyyyyy R5(config-keychain-key)#send-lifetime 00:00:00 Apr 1 2018 23:59:59 Jun 30 2018 R5(config-keychain-key)#accept-lifetime 23:55:00 Mar 31 2018 01:05:00 Jul 1 2018 R5(config-keychain-key)#end

Fix Text (F-102183r1_fix)

This requirement is not applicable for the DODIN Backbone.

Configure each key used for routing protocol authentication to have a lifetime of no more than 180 days as shown in the example below.

R5(config)#key chain OSPF_KEY_CHAIN
R5(config-keychain)#key 1
R5(config-keychain-key)#key-string xxxxxx
R5(config-keychain-key)#send-lifetime 00:00:00 Jan 1 2018 23:59:59 Mar 31 2018
R5(config-keychain-key)#accept-lifetime 00:00:00 Jan 1 2018 01:05:00 Apr 1 2018
R5(config-keychain-key)#exit
R5(config-keychain)#key 2
R5(config-keychain-key)#key-string yyyyyyy
R5(config-keychain-key)#send-lifetime 00:00:00 Apr 1 2018 23:59:59 Jun 30 2018
R5(config-keychain-key)#accept-lifetime 23:55:00 Mar 31 2018 01:05:00 Jul 1 2018
R5(config-keychain-key)#end