All local interactive user home directories defined in the /etc/passwd file must exist.

From Canonical Ubuntu 16.04 LTS Security Technical Implementation Guide

Associated with: CCI-000366

SV-90243r1_rule All local interactive user home directories defined in the /etc/passwd file must exist.

Vulnerability discussion

If a local interactive user has a home directory defined that does not exist, the user may be given access to the / directory as the current working directory upon logon. This could create a Denial of Service because the user would not be able to access their logon configuration files, and it may give them visibility to system files they normally would not be able to access.

Check content

Verify the assigned home directory of all local interactive users on the Ubuntu operating system exists. Check the home directory assignment for all local interactive non-privileged users with the following command: # ls -ld $(awk -F: '($3>=1000)&&($1!="nobody"){print $6}' /etc/passwd) drwxr-xr-x 2 smithj admin 4096 Jun 5 12:41 smithj Note: This may miss interactive users that have been assigned a privileged User ID (UID). Evidence of interactive use may be obtained from a number of log files containing system logon information. Check that all referenced home directories exist with the following command: # pwck -r user 'smithj': directory '/home/smithj' does not exist If any home directories referenced in "/etc/passwd" are returned as not defined, this is a finding.

Fix text

Create home directories to all local interactive users that currently do not have a home directory assigned. Use the following commands to create the user home directory assigned in "/etc/ passwd": Note: The example will be for the user smithj, who has a home directory of "/home/smithj", a User ID (UID) of "smithj", and a Group Identifier (GID) of "users assigned" in "/etc/passwd". # mkdir /home/smithj # chown smithj /home/smithj # chgrp users /home/smithj # chmod 0750 /home/smithj

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.