Linux distributions
TMA-ROCKY9-3.3.1.4
Ensure net.ipv4.conf.all.send_redirects is configured
Описание
ICMP Redirects are used to send routing information to other hosts. As a host itself does not act as a router (in a host only configuration), there is no need to send redirects. net.ipv4.conf.all.send_redirects controls sending of all IPv4 ICMP redirected packets on all interfaces. More information about the kernel parameter configuration files, their location, and load preference is available in the "Configure Network Kernel Parameters" section overview. Note: If this system is a router this recommendation is not applicable.
Как проверяется
Метод проверки: Команда оболочки
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 $f in configuration"; return 1;; esac; }; if chk net.ipv4.conf.all.send_redirects 0; then echo compliant; fi- Ожидаемый вывод
compliant
Как исправляется
Метод исправления: Рекомендация или патч инфраструктуры
1. Review all files being used by systemd sysctl and comment out or remove all net.ipv4.conf.all.send_redirects lines that are not net.ipv4.conf.all.send_redirects=0. Example script: #!/usr/bin/env bash { l_option="net.ipv4.conf.all.send_redirects" l_value="0" l_grep="${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 -- '^\h*#\h*\/…
Свойства
- Операционные системы
- rocky-9
- Теги
- cis-convertedkernellinuxsysctl
- Источник
- CIS Rocky Linux 9 Benchmark v3.0.0 - 3.3.1.4
Проверить этот хост
Выполните команду на компьютере, аудит которого вам разрешён. Сканирование работает только на чтение.
tmaegis scan --target linux