The Cisco switch must be configured to have Internet Control Message Protocol (ICMP) redirect messages disabled on all external interfaces.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-221085 | CISC-RT-000190 | SV-221085r999694_rule | Medium |
| Description |
| The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Switches automatically send ICMP messages under a wide variety of conditions. Redirect ICMP messages are commonly used by attackers for network mapping and diagnosis. |
| STIG | Date |
| Cisco NX OS Switch RTR Security Technical Implementation Guide | 2024-12-20 |
Details
| Check Text (C-22800r409744_chk) |
| Review the switch configuration to verify that the no ip redirects command has been configured on all external interfaces as shown in the example below: interface Ethernet2/7 no switchport ip address x.22.4.2/30 no ip redirects If ICMP Redirect messages are enabled on any external interfaces, this is a finding. |
| Fix Text (F-22789r409745_fix) |
| Disable ICMP redirects on all external interfaces as shown in the example below: SW1(config)# int e2/7 SW1(config-if)# no ip redirects |