Cis Gcp Cos 6.2.10

---
name: cis-gcp-cos-6.2.10
description: "Ensure users' dot files are not group or world writable"
category: cis-gcp-cos
version: "1.2.0"
author: cyberstrike-official
tags: [cis, gcp, container-optimized-os, user-accounts, dot-files]
cis_id: "6.2.10"
cis_benchmark: "CIS Google Container-Optimized OS Benchmark v1.2.0"
tech_stack: [gcp, linux]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# 6.2.10 Ensure users' dot files are not group or world writable (Automated)

## Description

While the system administrator can establish secure permissions for users' "dot" files, the users can easily override these.

## Rationale

Group or world-writable user configuration files may enable malicious users to steal or modify other users' data or to gain another user's system privileges.

## Audit Procedure

Run the following script and verify no results are returned:

```bash
#!/bin/bash

grep -E -v '^(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
    for file in $dir/.[A-Za-z0-9]*; do
      if [ ! -h "$file" -a -f "$file" ]; then
        fileperm=$(ls -ld $file | cut -f1 -d" ")

        if [ $(echo $fileperm | cut -c6)  != "-" ]; then
          echo "Group Write permission set on file $file"
        fi
        if [ $(echo $fileperm | cut -c9)  != "-" ]; then
          echo "Other Write permission set on file $file"
        fi
      fi
    done
  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 dot file permissions and determine the action to be taken in accordance with site policy.

## Additional Information

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

## CIS Controls

| Controls Version | Control                                               | IG 1 | IG 2 | IG 3 |
| ---------------- | ----------------------------------------------------- | ---- | ---- | ---- |
| v8               | 3.3 Configure Data Access Control Lists               | x    | x    | x    |
| v7               | 14.6 Protect Information through Access Control Lists | x    | x    | x    |

## Profile

- Level 2 - Server