The router must be configured to have Internet Control Message Protocol (ICMP) redirects disabled on all external interfaces.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-207155 | SRG-NET-000362 | SRG-NET-000362-RTR-000115 | SV-207155r856639_rule | 2025-09-10 | 5 |
Description
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.
ℹ️ Check
Review the device configuration to determine if controls have been defined to ensure the router does not send ICMP Redirect messages out to any external interfaces.
If ICMP Redirect messages are enabled on any external interfaces, this is a finding.
✔️ Fix
Disable ICMP redirects on all external interfaces.