SLES-15-040360 - The SUSE operating system must not allow interfaces to send Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages by default.

Information

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table, possibly revealing portions of the network topology.

Solution

Configure the SUSE operating system to not allow interfaces to perform IPv4 ICMP redirects by default by running the following command as an administrator:

> sudo sysctl -w net.ipv4.conf.default.send_redirects=0

If '0' is not the system's default value, add or update the following line in '/etc/sysctl.d/99-stig.conf':

> sudo sh -c 'echo 'net.ipv4.conf.default.send_redirects=0' >> /etc/sysctl.d/99-stig.conf'

> sudo sysctl --system

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_SLES_15_V2R2_STIG.zip

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b., CAT|II, CCI|CCI-000366, Rule-ID|SV-235022r991589_rule, STIG-ID|SLES-15-040360, Vuln-ID|V-235022

Plugin: Unix

Control ID: 08d609aba5e8ea2723343b5e29df785575425f91272703aaffd616fae6472ff8