CISC-RT-000150 - The Cisco router must be configured to have Gratuitous ARP disabled on all external interfaces.

Information

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.

Solution

Disable gratuitous ARP as shown in the example below:

R5(config)#no ip gratuitous-arps

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS_Router_Y22M07_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-5, CAT|II, CCI|CCI-002385, Rule-ID|SV-216563r531085_rule, STIG-ID|CISC-RT-000150, STIG-Legacy|SV-105665, STIG-Legacy|V-96527, Vuln-ID|V-216563

Plugin: Cisco

Control ID: e6fac35e86b7bdf2d50617f1bb9ba4e1246c3836725aa88f238ccd69a1ecdc85