cis-gcp-cos-6-2-12

name	cis-gcp-cos-6.2.12
description	Ensure no users have .netrc files
category	cis-gcp-cos
version	1.2.0
author	cyberstrike-official
tags	["cis","gcp","container-optimized-os","user-accounts","netrc"]
cis_id	6.2.12
cis_benchmark	CIS Google Container-Optimized OS Benchmark v1.2.0
tech_stack	["gcp","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

6.2.12 Ensure no users have .netrc files (Automated)

Description

The .netrc file contains data for logging into a remote host for file transfers via FTP.

Rationale

The .netrc file presents a significant security risk since it stores passwords in unencrypted form. Even if FTP is disabled, user accounts may have brought over .netrc files from other systems which could pose a risk to those systems.

Audit Procedure

Run the following script and verify no results are returned:

#!/bin/bash

grep -E -v '^(root|halt|sync|shutdown)' /etc/passwd | awk -F: '($7 != "'"$(which nologin)"'" && $7 != "/bin/false") { print $1 " " $6 }' | while read user dir; do
  if [ ! -d "$dir" ]; then
    echo "The home directory ($dir) of user $user does not exist."
  else
    if [ ! -h "$dir/.netrc" -a -f "$dir/.netrc" ]; then
      echo ".netrc file $dir/.netrc exists"
    fi
  fi
done

Expected Result

No results should be returned.

Remediation

Making global modifications to users' files without alerting the user community can result in unexpected outages and unhappy users. Therefore, it is recommended that a monitoring policy be established to report user .netrc files and determine the action to be taken in accordance with site policy.

Additional Information

On some distributions the /sbin/nologin should be replaced with .