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cis-gcp-cos-6.2.7

DevOps & Security
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Ensure all users' home directories exist

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Cloud_Providers/Google_Cloud_Platform/CIS_Google_Container-Optimized_OS_Benchmark_v1.2.0/cis-gcp-cos-6.2.7/SKILL.md

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6.2.7 Ensure all users' home directories exist (Automated)

Description

Users can be defined in /etc/passwd without a home directory or with a home directory that does not actually exist.

Rationale

If the user's home directory does not exist or is unassigned, the user will be placed in "/" and will not be able to write any files or have local environment variables set.

Audit Procedure

Run the following script and verify no results are returned:

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

Expected Result

No results should be returned.

Remediation

If any users' home directories do not exist, create them and make sure the respective user owns the directory. Users without an assigned home directory should be removed or assigned a home directory as appropriate.

Additional Information

The audit script checks all users UID 500 and above except nfsnobody. Some distributions split at UID 1000 instead, consult your documentation and/or the UID_MIN setting in /etc/login.defs to determine which is appropriate for you.

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

CIS Controls

Controls VersionControlIG 1IG 2IG 3
v75.1 Establish Secure Configurationsxxx

Profile

  • Level 2 - Server