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cis-ubuntu1204-v110-13-12

DevOps & Security
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Check That Users Are Assigned Valid Home Directories

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_12.04_LTS_Server_Benchmark_v1.1.0/cis-ubuntu1204-v110-13-12/SKILL.md

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13.12 Check That Users Are Assigned Valid Home Directories (Scored)

Profile Applicability

  • Level 1

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

Using Command Line

This script checks to make sure that home directories assigned in the /etc/passwd file exist.

#!/bin/bash
cat /etc/passwd | awk -F: '{ print $1 " " $3 " " $6 }' | while read user uid dir; do
if [ $uid -ge 500 -a ! -d "$dir" -a $user != "nfsnobody" -a $user != "nobody" ]; then
echo "The home directory ($dir) of user $user does not exist."
fi
done

Expected Result

No output should be returned. Any output indicates users with non-existent home directories.

Remediation

Using Command Line

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.

Default Value

Home directories are created automatically when using useradd -m or adduser.

References

  • CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

Profile

Level 1 - Scored