The Juniper router must be configured to have Gratuitous ARP disabled on all external interfaces.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-217021 | SRG-NET-000362-RTR-000111 | JUNI-RT-000150 | SV-217021r855889_rule | 2024-12-05 | 3 |
| 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. |
| ℹ️ Check |
|---|
| 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 |
|---|
| Disable gratuitous ARP on all external interfaces using the following command. [edit interfaces ge-1/1/0 ] delete gratuitous-arp-reply |