Linux distributions
TMA-ROCKY9-3.3.2.8
Ensure net.ipv6.conf.default.accept_ra is configured
Descrição
Routers periodically Multicast Router Advertisement (RA) messages to announce their availability and convey information to neighboring nodes that enable them to be automatically configured on the network. net.ipv6.conf.default.accept_ra controls accepting IPv6 RA messages on newly added network devices. 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 IPv6 has been disabled, this recommendation is not applicable.
Como é verificado
Método de auditoria: Comando 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 $f in configuration"; return 1;; esac; }; if chk net.ipv6.conf.default.accept_ra 0; then echo compliant; fi- Saída esperada
compliant
Como é corrigido
Método de correção: Orientação ou patch de infraestrutura
1. Review all files being used by systemd sysctl and comment out or remove all net.ipv6.conf.default.accept_ra lines that are not net.ipv6.conf.default.accept_ra=0. Example script: #!/usr/bin/env bash { l_option="net.ipv6.conf.default.accept_ra" l_value="0" l_grep="${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*\/[^#…
Propriedades
- Sistemas operacionais
- rocky-9
- Tags
- cis-convertedkernellinuxsysctl
- Referência
- CIS Rocky Linux 9 Benchmark v3.0.0 - 3.3.2.8
Verificar este host
Execute isto em uma máquina que você tenha permissão para auditar. A varredura é somente leitura.
tmaegis scan --target linux