Ubuntu 20.04 CIS STIG

This role is based on 18.04 migration. The tasks are correct in content, but have to be re-sorted to fit the 20.04 Benchmark. Contribution welcome.

Configure Ubuntu 20.04 machine to be CIS compliant. Level 1 and 2 findings will be corrected by default.

This role will make changes to the system that could break things. This is not an auditing tool but rather a remediation tool to be used after an audit has been conducted.

Based on CIS Ubuntu Linux 20.04 LTS Benchmark - v1.0.0 - 07-21-2020 .

IMPORTANT INSTALL STEP

If you want to install this via the ansible-galaxy command you'll need to run it like this:

ansible-galaxy install -p roles -r requirements.yml

With this in the file requirements.yml:

- src: https://github.com/florianutz/ubuntu2004_cis.git

Example Playbook

You can find an example playbook below. please read the documentation anyway and check the settings for your case. For example, the default settings uninstall the X server!

- name: Harden Server
  hosts: servers
  become: yes

  roles:
    - ubuntu2004_cis

To run the tasks in this repository, first create this file one level above the repository (i.e. the playbook .yml and the directory ubuntu2004_cis should be next to each other), then review the file defaults/main.yml and disable any rule/section you do not wish to execute.

Assuming you named the file site.yml, run it with:

ansible-playbook site.yml

Requirements

You should carefully read through the tasks to make sure these changes will not break your systems before running this playbook.

Role Variables

There are many role variables defined in defaults/main.yml. This list shows the most important.

ubuntu2004cis_notauto: Run CIS checks that we typically do NOT want to automate due to the high probability of breaking the system (Default: false)

ubuntu2004cis_section1: CIS - General Settings (Section 1) (Default: true)

ubuntu2004cis_section2: CIS - Services settings (Section 2) (Default: true)

ubuntu2004cis_section3: CIS - Network settings (Section 3) (Default: true)

ubuntu2004cis_section4: CIS - Logging and Auditing settings (Section 4) (Default: true)

ubuntu2004cis_section5: CIS - Access, Authentication and Authorization settings (Section 5) (Default: true)

ubuntu2004cis_section6: CIS - System Maintenance settings (Section 6) (Default: true)

Disable all selinux functions

ubuntu2004cis_selinux_disable: false

Service variables

####These control whether a server should or should not be allowed to continue to run these services

ubuntu2004cis_avahi_server: false  
ubuntu2004cis_cups_server: false  
ubuntu2004cis_dhcp_server: false  
ubuntu2004cis_ldap_server: false  
ubuntu2004cis_telnet_server: false  
ubuntu2004cis_nfs_server: false  
ubuntu2004cis_rpc_server: false  
ubuntu2004cis_ntalk_server: false  
ubuntu2004cis_rsyncd_server: false  
ubuntu2004cis_tftp_server: false  
ubuntu2004cis_rsh_server: false  
ubuntu2004cis_nis_server: false  
ubuntu2004cis_snmp_server: false  
ubuntu2004cis_squid_server: false  
ubuntu2004cis_smb_server: false  
ubuntu2004cis_dovecot_server: false  
ubuntu2004cis_httpd_server: false  
ubuntu2004cis_vsftpd_server: false  
ubuntu2004cis_named_server: false  
ubuntu2004cis_bind: false  
ubuntu2004cis_vsftpd: false  
ubuntu2004cis_httpd: false  
ubuntu2004cis_dovecot: false  
ubuntu2004cis_samba: false  
ubuntu2004cis_squid: false  
ubuntu2004cis_net_snmp: false  

Designate server as a Mail server

ubuntu2004cis_is_mail_server: false

####System network parameters (host only OR host and router) ubuntu2004cis_is_router: false

####IPv6 required ubuntu2004cis_ipv6_required: true

AIDE

ubuntu2004cis_config_aide: true

AIDE cron settings

ubuntu2004cis_aide_cron:
  cron_user: root
  cron_file: /etc/crontab
  aide_job: '/usr/sbin/aide --check'
  aide_minute: 0
  aide_hour: 5
  aide_day: '*'
  aide_month: '*'
  aide_weekday: '*'  

Set to 'true' if X Windows is needed in your environment

ubuntu2004cis_xwindows_required: no

Client application requirements

ubuntu2004cis_openldap_clients_required: false
ubuntu2004cis_telnet_required: false
ubuntu2004cis_talk_required: false  
ubuntu2004cis_rsh_required: false
ubuntu2004cis_ypbind_required: false
ubuntu2004cis_rpc_required: false

Time Synchronization

ubuntu2004cis_time_synchronization: chrony
ubuntu2004cis_time_Synchronization: ntp

ubuntu2004cis_time_synchronization_servers:
  - uri: "0.pool.ntp.org"
    config: "minpoll 8"
  - uri: "1.pool.ntp.org"
    config: "minpoll 8"
  - uri: "2.pool.ntp.org"
    config: "minpoll 8"
  - uri: "3.pool.ntp.org"
    config: "minpoll 8"

- name: "SCORED | 1.1.5 | PATCH | Ensure noexec option set on /tmp partition"

It is not implemented, noexec for /tmp will disrupt apt. /tmp contains executable scripts during package installation

1.5.3 | PATCH | Ensure authentication required for single user mode

It is disabled by default as it is setting random password for root. To enable it set:

ubuntu2004cis_rule_1_5_3: true

To use other than random password:

ubuntu2004cis_root_password: 'new password'

3.4.2 | PATCH | Ensure /etc/hosts.allow is configured

ubuntu2004cis_host_allow:
  - "10.0.0.0/255.0.0.0"  
  - "172.16.0.0/255.240.0.0"  
  - "192.168.0.0/255.255.0.0"    

ubuntu2004cis_firewall: firewalld
ubuntu2004cis_firewall: iptables

5.3.1 | PATCH | Ensure password creation requirements are configured

ubuntu2004cis_pwquality:
  - key: 'minlen'
    value: '14'
  - key: 'dcredit'
    value: '-1'
  - key: 'ucredit'
    value: '-1'
  - key: 'ocredit'
    value: '-1'
  - key: 'lcredit'
    value: '-1'

Dependencies

Developed and testes with Ansible 2.10

Tags

Many tags are available for precise control of what is and is not changed.

Some examples of using tags:

    # Audit and patch the site
    ansible-playbook site.yml --tags="patch"

License

MIT

other

This repo originated from work done by MindPointGroup