Ensure kernel module loading and unloading is collected

LowLevel 2Automatedlinux

Description

Monitor the loading and unloading of kernel modules. The programs insmod (install a kernel module), rmmod (remove a kernel module), and modprobe (a more sophisticated program to load and unload modules, as well as some other features) control loading and unloading of modules. The init_module (load a module) and delete_module (delete a module) system calls control loading and unloading of modules. Any execution of the loading and unloading module programs and system calls will trigger an audit record with an identifier of "modules". Note: Reloading the auditd config to set active settings requi

How it is checked

Audit method: Shell command

shell

alt0() { command -v grep >/dev/null 2>&1 || { echo "step1: grep not installed"; return 1; }; o=$(bash -c 'grep modules /etc/audit/rules.d/*.rules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/insmod -p x -k modules' || { echo step1: missing '-w /sbin/insmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/rmmod -p x -k modules' || { echo step1: missing '-w /sbin/rmmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/modprobe -p x -k modules' || { echo step1: missing '-w /sbin/modprobe -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b32 -S init_module -S delete_module -k modules' || { echo step1: missing '-a always,exit -F arch=b32 -S init_module -S delete_module -'; return 1; }; command -v auditctl >/dev/null 2>&1 || { echo "step2: auditctl not installed"; return 1; }; command -v grep >/dev/null 2>&1 || { echo "step2: grep not installed"; return 1; }; o=$(bash -c 'auditctl -l | grep modules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/insmod -p x -k modules' || { echo step2: missing '-w /sbin/insmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/rmmod -p x -k modules' || { echo step2: missing '-w /sbin/rmmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/modprobe -p x -k modules' || { echo step2: missing '-w /sbin/modprobe -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b32 -S init_module,delete_module -F key=modules On a 64 bit system run the following commands:' || { echo step2: missing '-a always,exit -F arch=b32 -S init_module,delete_module -F k'; return 1; }; command -v grep >/dev/null 2>&1 || { echo "step3: grep not installed"; return 1; }; o=$(bash -c 'grep modules /etc/audit/rules.d/*.rules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/modules.rules:-w /sbin/insmod -p x -k modules' || { echo step3: missing '/etc/audit/rules.d/modules.rules:-w /sbin/insmod -p x -k mod'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/modules.rules:-w /sbin/rmmod -p x -k modules' || { echo step3: missing '/etc/audit/rules.d/modules.rules:-w /sbin/rmmod -p x -k modu'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/modules.rules:-w /sbin/modprobe -p x -k modules' || { echo step3: missing '/etc/audit/rules.d/modules.rules:-w /sbin/modprobe -p x -k m'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/modules.rules:-a always,exit -F arch=b64 -S init_module -S delete_module -k' || { echo step3: missing '/etc/audit/rules.d/modules.rules:-a always,exit -F arch=b64 '; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- modules || { echo step3: missing modules; return 1; }; command -v auditctl >/dev/null 2>&1 || { echo "step4: auditctl not installed"; return 1; }; command -v grep >/dev/null 2>&1 || { echo "step4: grep not installed"; return 1; }; o=$(bash -c 'auditctl -l | grep modules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/insmod -p x -k modules' || { echo step4: missing '-w /sbin/insmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/rmmod -p x -k modules' || { echo step4: missing '-w /sbin/rmmod -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /sbin/modprobe -p x -k modules' || { echo step4: missing '-w /sbin/modprobe -p x -k modules'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b64 -S init_module,delete_module -F key=modules' || { echo step4: missing '-a always,exit -F arch=b64 -S init_module,delete_module -F k'; return 1; }; }; if alt0; then echo compliant; fi

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

For 32 bit systems Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules Example: vi /etc/audit/rules.d/modules.rules and add the following lines: -w /sbin/insmod -p x -k modules -w /sbin/rmmod -p x -k modules -w /sbin/modprobe -p x -k modules -a always,exit -F arch=b32 -S init_module -S delete_module -k modules For 64 bit systems Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules Example: vi /etc/audit/rules.d/modules.rules and add the following lines: -w /sbin/insmod -p x -k modules -w /sbin/rmmod -p x -k modules -w /sbin/modprobe -p x -k modules -a always,exit -F arch=b64 -S init_module -S delete_module -k modules

Properties

Operating systems: sles-12
Tags: cis-convertedlinux
Reference: CIS SUSE Linux Enterprise 12 Benchmark v3.2.0 - 4.1.16

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target linux --level 2