Ensure packet redirect sending is disabled

MediumLevel 1Automatedlinux

Description

Kernel parameter net.ipv4.conf.all.send_redirects should be 0.

How it is checked

Audit method: Shell command

shell

sysctl -n net.ipv4.conf.all.send_redirects

Expected output: 0

How it is fixed

Fix method: Shell command

shell

sysctl -w net.ipv4.conf.all.send_redirects=0 && printf 'net.ipv4.conf.all.send_redirects = 0\n' > /etc/sysctl.d/60-tmaegis-net_ipv4_conf_all_send_redirects.conf

Properties

Operating systems: ubuntu-22.04, ubuntu-24.04, rocky-9
Tags: kernelsysctlnetwork
Reference: CIS Linux Benchmark - Network Configuration / Kernel Parameters (verify section number for your distro release)

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target linux