The Cisco perimeter switch must be configured to have Cisco Discovery Protocol (CDP) disabled on all external interfaces.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-221097 | CISC-RT-000370 | SV-221097r999706_rule | 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 NX OS Switch RTR Security Technical Implementation Guide | 2024-12-20 |
Details
| Check Text (C-22812r409780_chk) |
| Step 1: Verify CDP is not enabled globally via the command no cdp enable By default CDP is enabled globally; hence, the command cdp enable 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 Ethernet2/2 description link to DISN no switchport no cdp enable Note: By default CDP is enabled on all interfaces if CDP is enabled globally. If CDP is enabled on any external interface, this is a finding. |
| Fix Text (F-22801r409781_fix) |
| Disable CDP on all external interfaces via no cdp enable interface command or disable CDP globally via no cdp enable command. |