Linux distributions
TMA-ALMA9-3.3.1.7
Ensure net.ipv4.icmp_echo_ignore_broadcasts is configured
Opis
net.ipv4.icmp_echo_ignore_broadcasts controls if all ICMP echo and timestamp requests to broadcast and multicast addresses are ignored. More information about the kernel parameter configuration files, their location, and load preference is available in the "Configure Network Kernel Parameters" section overview.
Kako se proverava
Metod provere: Komanda ljuske
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 $f in configuration"; return 1;; esac; }; if chk net.ipv4.icmp_echo_ignore_broadcasts 1; then echo compliant; fi- Očekivani izlaz
compliant
Kako se ispravlja
Metod ispravke: Smernica ili zakrpa infrastrukture
1. Review all files being used by systemd sysctl and comment out or remove all net.ipv4.icmp_echo_ignore_broadcasts lines that are not net.ipv4.icmp_echo_ignore_broadcasts=1. Example script: #!/usr/bin/env bash { l_option="net.ipv4.icmp_echo_ignore_broadcasts" l_value="1" l_grep="${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 --…
Svojstva
- Operativni sistemi
- almalinux-9
- Oznake
- cis-convertedkernellinuxsysctl
- Referenca
- CIS AlmaLinux OS 9 Benchmark v3.0.0 - 3.3.1.7
Proverite ovaj računar
Pokrenite ovo na računaru za koji imate dozvolu za proveru. Skeniranje radi u režimu samo za čitanje.
tmaegis scan --target linux