Cisco IOS Switch RTR STIG Version Comparison

There are 9 differences between versions v2 r3 (April 27, 2023) (the "left" version) and v2 r5 (Oct. 25, 2023) (the "right" version).

Check CISC-RT-000020 was removed from the benchmark in the "right" version. The text below reflects the old wording.

This check's original form is available here.

Title

The Cisco switch must be configured to implement message authentication for all control plane protocols.

Check Content

Review the switch configuration. Verify that authentication is enabled for all routing protocols. The configuration examples below depict OSPF and EIGRP authentication. EIGRP example: key chain EIGRP_KEY key 1 key-string xxxxxxx … … … interface GigabitEthernet0/0 no switchport ip address x.x.x.x 255.255.255.0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 EIGRP_KEY OSPF example: interface GigabitEthernet0/0 no switchport ip address x.x.x.x 255.255.255.0 ip ospf authentication-key xxxxx If authentication is not enabled on all routing protocols, this is a finding.

Discussion

A rogue switch could send a fictitious routing update to convince a site's perimeter switch to send traffic to an incorrect or even a rogue destination. This diverted traffic could be analyzed to learn confidential information about the site's network or used to disrupt the network's ability to communicate with other networks. This is known as a "traffic attraction attack" and is prevented by configuring neighbor switch authentication for routing updates. This requirement applies to all IPv4 and IPv6 protocols that are used to exchange routing or packet forwarding information; this includes all Interior Gateway Protocols (such as OSPF, EIGRP, and IS-IS) and Exterior Gateway Protocols (such as BGP), MPLS-related protocols (such as LDP), and multicast-related protocols.

Fix

Configure authentication to be enabled for every protocol that affects the routing or forwarding tables. The example configuration commands below enables OSPF and EIGRP authentication. EIGRP example: SW1(config)#key chain EIGRP_KEY SW1(config-keychain)#key 1 SW1(config-keychain-key)#key-string xxxxx SW1(config-keychain-key)#exit SW1(config-keychain)#exit SW1(config)#int g0/0 SW1(config-if)#ip authentication mode eigrp 1 md5 SW1(config-if)#ip authentication key-chain eigrp 1 EIGRP_KEY SW1(config-if)#end OSPF example: SW1(config)#int g0/0 SW1(config-if)#ip ospf authentication-key xxxxx SW1(config-if)#end