Linux distributions
TMA-ROCKY9-3.3.1.7
Ensure net.ipv4.icmp_echo_ignore_broadcasts is configured
說明
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.
檢查方式
稽核方法: Shell 指令
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 $f in configuration"; return 1;; esac; }; if chk net.ipv4.icmp_echo_ignore_broadcasts 1; then echo compliant; fi- 預期輸出
compliant
修補方式
修補方法: 操作指南或基礎設施修補檔
1. Review all files being used by systemd sysctl and comment out or remove all net.ipv4.icmp_echo_ignore_broadcasts lines that are not net.ipv4.icmp_echo_ignore_broadcasts=1. Example script: #!/usr/bin/env bash { l_option="net.ipv4.icmp_echo_ignore_broadcasts" l_value="1" l_grep="${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 --…
屬性
- 作業系統
- rocky-9
- 標籤
- cis-convertedkernellinuxsysctl
- 參考資料
- CIS Rocky Linux 9 Benchmark v3.0.0 - 3.3.1.7
檢查此主機
請在您有權稽核的機器上執行此指令。掃描為唯讀操作。
tmaegis scan --target linux