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 system must ignore ICMPv4 redirect messages by default.


Overview

Finding ID Version Rule ID IA Controls Severity
V-38533 RHEL-06-000091 SV-50334r3_rule Low
Description
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
STIG Date
Red Hat Enterprise Linux 6 Security Technical Implementation Guide 2018-03-01

Details

Check Text ( C-46091r2_chk )
The status of the "net.ipv4.conf.default.accept_redirects" kernel parameter can be queried by running the following command:

$ sysctl net.ipv4.conf.default.accept_redirects

The output of the command should indicate a value of "0". If this value is not the default value, investigate how it could have been adjusted at runtime, and verify it is not set improperly in "/etc/sysctl.conf".

$ grep net.ipv4.conf.default.accept_redirects /etc/sysctl.conf

If the correct value is not returned, this is a finding.
Fix Text (F-43481r1_fix)
To set the runtime status of the "net.ipv4.conf.default.accept_redirects" kernel parameter, run the following command:

# sysctl -w net.ipv4.conf.default.accept_redirects=0

If this is not the system's default value, add the following line to "/etc/sysctl.conf":

net.ipv4.conf.default.accept_redirects = 0