The SUSE operating system must not respond to Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) echoes sent to a broadcast address.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-217290 | SLES-12-030380 | SV-217290r991589_rule | CCI-000366 | medium |
| Description | ||||
| Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks. | ||||
| STIG | Date | |||
| SUSE Linux Enterprise Server 12 Security Technical Implementation Guide | 2025-05-14 | |||
Details
Check Text (C-217290r991589_chk)
Verify the SUSE operating system does not accept IPv4 source-routed packets.
Check the value of the accept source route variable with the following command:
# sysctl net.ipv4.icmp_echo_ignore_broadcasts
net.ipv4.icmp_echo_ignore_broadcasts = 1
If the returned line does not have a value of "1" this is a finding.
Fix Text (F-18516r370027_fix)
Configure the SUSE operating system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value):
net.ipv4.icmp_echo_ignore_broadcasts = 1
Run the following command to apply this value:
# sysctl --system