V-217024

Discussion

The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Routers automatically send ICMP messages under a wide variety of conditions. Redirect ICMP messages are commonly used by attackers for network mapping and diagnosis.

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Review the device configuration to determine if it has been configured to ensure the router does not send ICMP Redirect messages out to any external interface.

interfaces {
    ge-1/0/0 {
        unit 0 {
            family inet {
                no-redirects;
                address 11.1.12.2/24;
            }
        }
    }
    ge-1/1/0  {
        unit 0 {
            family inet {
                no-redirects;
                address 11.1.23.2/24;
            }
        }
    }

If ICMP Redirect messages are enabled on any external interfaces, this is a finding.