TMAegisBêta
Plus de règles pour linux

Linux distributions

TMA-ALMA9-3.3.1.20

Ensure net.ipv4.conf.default.route_localnet is configured

MoyenneNiveau 1Automatiséelinux

Description

The net.ipv4.conf.default.route_localnet flag sets, for newly added network interfaces, whether the system may use 127/8 for local routing purposes; when set to 0 the system continues to treat loopback addresses as martian source or destination while routing. More information about the kernel parameter configuration files, their location, and load preference is available in the "Configure Network Kernel Parameters" section overview.

Méthode de vérification

Méthode d'audit: Commande shell

shell
chk() { p=$1; allowed=" $2 "; case $p in net.ipv6.*) [ -d /proc/sys/net/ipv6 ] || return 0;; esac; v=$(sysctl -n "$p" 2>/dev/null) || { echo "$p: not available"; return 1; }; case "$allowed" in *" $v "*) ;; *) echo "$p is $v (running)"; return 1;; esac; sd=$(readlink -e /lib/systemd/systemd-sysctl || readlink -e /usr/lib/systemd/systemd-sysctl); f=$("$sd" --cat-config 2>/dev/null | grep -Po "^\h*${p//./\.}\h*=\h*\K\H+" | tail -n1); [ -n "$f" ] || { echo "$p is not set in any sysctl configuration file"; return 1; }; case "$allowed" in *" $f "*) ;; *) echo "$p is $f in configuration"; return 1;; esac; }; if chk net.ipv4.conf.default.route_localnet 0; then echo compliant; fi
Sortie attendue
compliant

Méthode de correction

Méthode de correction: Recommandation ou correctif d'infrastructure

Review all files being used by systemd sysctl and comment out or remove all net.ipv4.conf.default.route_localnet lines that are not net.ipv4.conf.default.route_localnet = 0. Example script #!/usr/bin/env bash { l_option="net.ipv4.conf.default.route_localnet" l_value="0" l_grep="${l_option//./(\\.|\\/)}" a_files=() l_systemdsysctl="$(readlink -e /lib/systemd/systemd-sysctl \ || readlink -e /usr/lib/systemd/systemd-sysctl)" a_files+=("/etc/sysctl.conf") while IFS= read -r l_fname; do l_file="$(readlink -e "${l_fname//# /}")" [ -n "$l_file" ] && ! grep -Psiq -- '(^|\h+)'"$l_file"'\b' \ <<< "${a_files[*]}" && a_files+=("$l_file") done < <("$l_systemdsysctl" --cat-config | tac | \ grep -Psio -- '…

Propriétés

Systèmes d'exploitation
almalinux-9
Étiquettes
cis-convertedkernellinuxsysctl
Référence
CIS AlmaLinux OS 9 Benchmark v3.0.0 - 3.3.1.20

Vérifier cet hôte

Exécutez cette commande sur une machine que vous êtes autorisé à auditer. L'analyse est en lecture seule.

shell
tmaegis scan --target linux