The router must be configured to have Gratuitous ARP disabled on all external interfaces.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-207151 | SRG-NET-000362-RTR-000111 | SV-207151r856635_rule | Medium |
| 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. |
| STIG | Date |
| Router Security Requirements Guide | 2024-05-28 |
Details
| Check Text (C-7412r382436_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. |