Title

Ubuntu 24.04 LTS must not allow unattended or automatic login via SSH. (Cat I impact)

Discussion

Failure to restrict system access to authenticated users negatively impacts Ubuntu 24.04 LTS security.

Check Content

Verify unattended or automatic login via SSH is disabled with the following command: $ egrep -r '(Permit(.*?)(Passwords|Environment))' /etc/ssh/sshd_config PermitEmptyPasswords no PermitUserEnvironment no If the "PermitEmptyPasswords" or "PermitUserEnvironment" keywords are set to a value other than "no", are commented out, are both missing, or conflicting results are returned, this is a finding.

Fix Text

Configure Ubuntu 24.04 LTS to allow the SSH daemon to not allow unattended or automatic login to the system. Add or edit the following lines in the "/etc/ssh/sshd_config" file: PermitEmptyPasswords no PermitUserEnvironment no Restart the SSH daemon for the changes to take effect: $ sudo systemctl restart sshd.service

Additional Identifiers

Rule ID: SV-270717r1067177_rule

Vulnerability ID: V-270717

Group Title: SRG-OS-000480-GPOS-00229

Expert Comments

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