Ensure kernel.kptr_restrict is configured

OrtaDüzey 1Otomatiklinux

Açıklama

kernel.kptr_restrict sets whether restrictions are placed on exposing kernel addresses via /proc and other interfaces. • kptr_restrict = 0 - The address is hashed before printing. (equivalent to %p.) • kptr_restrict = 1 - kernel pointers printed using the %pK format specifier will be replaced with 0's. • kptr_restrict = 2 - kernel pointers printed using %pK will be replaced with 0's regardless of privileges. More information about the kernel parameter configuration files, their location, and load preference is available in the section overview.

Nasıl denetlenir

Denetim yöntemi: Kabuk komutu

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 kernel.kptr_restrict '1 2'; then echo compliant; fi

Beklenen çıktı: compliant

Nasıl düzeltilir

Düzeltme yöntemi: Kılavuz veya altyapı yaması

1. Review all files being used by systemd sysctl and comment out or remove all kernel.kptr_restrict lines that are not kernel.kptr_restrict=1 or kernel.kptr_restrict=2. Example script: #!/usr/bin/env bash { l_option="kernel.kptr_restrict" l_value="(1|2)" 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 -Pio '^\h*#\h*\/[^#\n\r\h]…

Özellikler

İşletim sistemleri: rocky-9
Etiketler: cis-convertedkernellinuxsysctl
Referans: CIS Rocky Linux 9 Benchmark v3.0.0 - 1.5.5

Bu ana makineyi denetle

Bunu denetleme izniniz olan bir makinede çalıştırın. Tarama salt okunurdur.

shell

tmaegis scan --target linux