Ensure changes to system administration scope (sudoers) is collected

LowLevel 2Automatedlinux

Description

Monitor scope changes for system administrators. If the system has been properly configured to force system administrators to log in as themselves first and then use the sudo command to execute privileged commands, it is possible to monitor changes in scope. The file /etc/sudoers or a file in the /etc/sudoers.d directory will be written to when the file or its attributes have changed. Note: Reloading the auditd config to set active settings may require a system reboot.

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=$(bash -c 'grep scope /etc/audit/rules.d/*.rules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/scope.rules:-w /etc/sudoers -p wa -k scope' || { echo step1: missing '/etc/audit/rules.d/scope.rules:-w /etc/sudoers -p wa -k scop'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '/etc/audit/rules.d/scope.rules:-w /etc/sudoers.d/ -p wa -k scope' || { echo step1: missing '/etc/audit/rules.d/scope.rules:-w /etc/sudoers.d/ -p wa -k s'; return 1; }; command -v auditctl >/dev/null 2>&1 || { echo "step2: auditctl not installed"; return 1; }; command -v grep >/dev/null 2>&1 || { echo "step2: grep not installed"; return 1; }; o=$(bash -c 'auditctl -l | grep scope' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /etc/sudoers -p wa -k scope' || { echo step2: missing '-w /etc/sudoers -p wa -k scope'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-w /etc/sudoers.d -p wa -k scope' || { echo step2: missing '-w /etc/sudoers.d -p wa -k scope'; return 1; }; }; if alt0; then echo compliant; fi

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules Example: vi /etc/audit/rules.d/scope.rules and add the following lines: -w /etc/sudoers -p wa -k scope -w /etc/sudoers.d/ -p wa -k scope

Properties

Operating systems: sles-12
Tags: cis-convertedlinux
Reference: CIS SUSE Linux Enterprise 12 Benchmark v3.2.0 - 4.1.14

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