UCF STIG Viewer Logo
Changes are coming to https://stigviewer.com. Take our survey to help us understand your usage and how we can better serve you in the future.
Take Survey

The SUSE operating system must prevent Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages from being accepted.


Overview

Finding ID Version Rule ID IA Controls Severity
V-77493 SLES-12-030390 SV-92189r3_rule Medium
Description
ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
STIG Date
SLES 12 Security Technical Implementation Guide 2019-03-12

Details

Check Text ( C-77053r1_chk )
Verify the SUSE operating system does not respond to IPv4 ICMP echoes sent to a broadcast address.

Check the value of the "icmp_echo_ignore_broadcasts" 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-84135r3_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