The Juniper router must be configured to have Gratuitous ARP disabled on all external interfaces.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-217021JUNI-RT-000150SV-217021r855889_ruleCCI-002385medium
Description
A gratuitous ARP is an ARP broadcast in which the source and destination MAC addresses are the same. It is used to inform the network about a host IP address. A spoofed gratuitous ARP message can cause network mapping information to be stored incorrectly, causing network malfunction.
STIGDate
Juniper Router RTR Security Technical Implementation Guide2024-12-05

Details

Check Text (C-217021r855889_chk)

Review the configuration to determine if gratuitous ARP is disabled on all external interfaces. The following command should not be set to any interface: gratuitous-arp-reply If gratuitous ARP is enabled on any external interface, this is a finding.

Fix Text (F-18248r296932_fix)

Disable gratuitous ARP on all external interfaces using the following command. [edit interfaces ge-1/1/0 ] delete gratuitous-arp-reply