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

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-207151SRG-NET-000362-RTR-000111SV-207151r856635_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
Router Security Requirements Guide2024-05-28

Details

Check Text (C-207151r856635_chk)

Review the configuration to determine if gratuitous ARP is disabled on all external interfaces. If gratuitous ARP is enabled on any external interface, this is a finding.

Fix Text (F-7412r382437_fix)

Disable gratuitous ARP on all external interfaces.