SV-204615r603261_rule
V-204615
SRG-OS-000480-GPOS-00227
RHEL-07-040641
CAT II
10
Set the system to ignore IPv4 ICMP redirect messages by adding the following line to "/etc/sysctl.conf" or a configuration file in the /etc/sysctl.d/ directory (or modify the line to have the required value):
net.ipv4.conf.all.accept_redirects = 0
Issue the following command to make the changes take effect:
# sysctl --system
Verify the system ignores IPv4 ICMP redirect messages.
# grep 'net.ipv4.conf.all.accept_redirects' /etc/sysctl.conf /etc/sysctl.d/*
If " net.ipv4.conf.all.accept_redirects " is not configured in the /etc/sysctl.conf file or in the /etc/sysctl.d/ directory, is commented out, or does not have a value of "0", this is a finding.
Check that the operating system implements the "accept_redirects" variables with the following command:
# /sbin/sysctl -a | grep 'net.ipv4.conf.all.accept_redirects'
net.ipv4.conf.all.accept_redirects = 0
If the returned line does not have a value of "0", this is a finding.
V-204615
False
RHEL-07-040641
Verify the system ignores IPv4 ICMP redirect messages.
# grep 'net.ipv4.conf.all.accept_redirects' /etc/sysctl.conf /etc/sysctl.d/*
If " net.ipv4.conf.all.accept_redirects " is not configured in the /etc/sysctl.conf file or in the /etc/sysctl.d/ directory, is commented out, or does not have a value of "0", this is a finding.
Check that the operating system implements the "accept_redirects" variables with the following command:
# /sbin/sysctl -a | grep 'net.ipv4.conf.all.accept_redirects'
net.ipv4.conf.all.accept_redirects = 0
If the returned line does not have a value of "0", this is a finding.
M
2899