Information
RHEL 10 must use a reverse-path filter for Internet Protocol version 4 (IPv4) network traffic when possible by default.
GROUP ID: V-281348RULE ID: SV-281348r1167194
Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface on which they were received. It must not be used on systems that are routers for complicated networks but is helpful for end hosts and routers serving small networks.
Satisfies: SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00079
Solution
Configure RHEL 10 to use reverse path filtering on IPv4 interfaces by default.
Create a configuration file if it does not already exist:
$ sudo vi /etc/sysctl.d/ipv4_rp_filter.conf
Add the following line to the file:
net.ipv4.conf.default.rp_filter = 1
Reload settings from all system configuration files with the following command:
$ sudo sysctl --system