The Cisco perimeter router must be configured to have Cisco Discovery Protocol (CDP) disabled on all external interfaces.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-216765 | CISC-RT-000370 | SV-216765r856443_rule | CCI-002403 | low |
| Description | ||||
| CDP is a Cisco proprietary neighbor discovery protocol used to advertise device capabilities, configuration information, and device identity. CDP is media- and protocol-independent as it runs over layer 2; therefore, two network nodes that support different layer 3 protocols can still learn about each other. Allowing CDP messages to reach external network nodes provides an attacker a method to obtain information of the network infrastructure that can be useful to plan an attack. | ||||
| STIG | Date | |||
| Cisco IOS XR Router RTR Security Technical Implementation Guide | 2024-08-22 | |||
Details
Check Text (C-216765r856443_chk)
This requirement is not applicable for the DODIN Backbone.
Step 1: Verify if CDP is enabled globally via the cdp command as shown below.
hostname R3
cdp
By default CDP is disabled globally; hence, the command cdp run will not be shown in the configuration. If CDP is enabled, proceed to step 2.
Step 2: Verify CDP is not enabled on any external interface as shown in the example below.
interface GigabitEthernet0/0/0/1
cdp
ipv4 address x.1.34.3 255.255.255.252
If CDP is enabled on any external interface, this is a finding.
Fix Text (F-17995r288679_fix)
This requirement is not applicable for the DODIN Backbone.
Disable CDP on all external interfaces via no cdp command or disable CDP globally via no cdp command.