CIS Ubuntu 14.04 LTS - 6.2.12 Ensure no users have .netrc files

6.2.12 Ensure no users have .netrc files (Scored)

Profile Applicability

• Level 1 - Server
• Level 1 - Workstation

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

cat /etc/passwd | egrep -v '^(root|halt|sync|shutdown)' | awk -F: '($7 != "/sbin/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 output 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.

Default Value

Not applicable.

References

None

CIS Controls

16.14 Encrypt/Hash All Authentication Files And Monitor Their Access - Verify that all authentication files are encrypted or hashed and that these files cannot be accessed without root or administrator privileges. Audit all access to password files in the system.

Profile

• Level 1