The Ubuntu operating system must use SSH to protect the confidentiality and integrity of transmitted information.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-238215	UBTU-20-010042	SV-238215r653820_rule		High

Description
Without protection of the transmitted information, confidentiality and integrity may be compromised because unprotected communications can be intercepted and either read or altered. This requirement applies to both internal and external networks and all types of information system components from which information can be transmitted (e.g., servers, mobile devices, notebook computers, printers, copiers, scanners, and facsimile machines). Communication paths outside the physical protection of a controlled boundary are exposed to the possibility of interception and modification. Protecting the confidentiality and integrity of organizational information can be accomplished by physical means (e.g., employing physical distribution systems) or by logical means (e.g., employing cryptographic techniques). If physical means of protection are employed, then logical means (cryptography) do not have to be employed, and vice versa. Satisfies: SRG-OS-000423-GPOS-00187, SRG-OS-000425-GPOS-00189, SRG-OS-000426-GPOS-00190

Description

Without protection of the transmitted information, confidentiality and integrity may be compromised because unprotected communications can be intercepted and either read or altered. This requirement applies to both internal and external networks and all types of information system components from which information can be transmitted (e.g., servers, mobile devices, notebook computers, printers, copiers, scanners, and facsimile machines). Communication paths outside the physical protection of a controlled boundary are exposed to the possibility of interception and modification. Protecting the confidentiality and integrity of organizational information can be accomplished by physical means (e.g., employing physical distribution systems) or by logical means (e.g., employing cryptographic techniques). If physical means of protection are employed, then logical means (cryptography) do not have to be employed, and vice versa. Satisfies: SRG-OS-000423-GPOS-00187, SRG-OS-000425-GPOS-00189, SRG-OS-000426-GPOS-00190

STIG	Date
Canonical Ubuntu 20.04 LTS Security Technical Implementation Guide	2021-03-23

Details

Check Text ( C-41425r653818_chk )
Verify the SSH package is installed with the following command: $ sudo dpkg -l \| grep openssh ii openssh-client 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) client, for secure access to remote machines ii openssh-server 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) server, for secure access from remote machines ii openssh-sftp-server 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) sftp server module, for SFTP access from remote machines If the "openssh" server package is not installed, this is a finding. Verify the "sshd.service" is loaded and active with the following command: $ sudo systemctl status sshd.service \| egrep -i "(active\|loaded)" Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled) Active: active (running) since Thu 2019-01-24 22:52:58 UTC; 1 weeks 3 days ago If "sshd.service" is not active or loaded, this is a finding.

Check Text ( C-41425r653818_chk )

Verify the SSH package is installed with the following command:

$ sudo dpkg -l | grep openssh
ii openssh-client 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) client, for secure access to remote machines
ii openssh-server 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) server, for secure access from remote machines
ii openssh-sftp-server 1:7.6p1-4ubuntu0.1 amd64 secure shell (SSH) sftp server module, for SFTP access from remote machines

If the "openssh" server package is not installed, this is a finding.

Verify the "sshd.service" is loaded and active with the following command:

$ sudo systemctl status sshd.service | egrep -i "(active|loaded)"
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2019-01-24 22:52:58 UTC; 1 weeks 3 days ago

If "sshd.service" is not active or loaded, this is a finding.

Fix Text (F-41384r653819_fix)
Install the "ssh" meta-package on the system with the following command: $ sudo apt install ssh Enable the "ssh" service to start automatically on reboot with the following command: $ sudo systemctl enable sshd.service ensure the "ssh" service is running $ sudo systemctl start sshd.service