This role applies security hardening configurations to systems running Debian 11 (Bullseye). These configurations include:

• AIDE
• AppArmor
• Apt Package Manager
• Auditd + LAUREL
• ClamAV
• Fail2Ban
• Firewalld + nftables
• Hardened_Malloc
• Haveged
• Kernel tuning
• OpenSSH
• SysmonForLinux

Many of these configurations can be enabled/disabled in defaults/main.yml

Requires Ansible 2.10 or later. This role has only been tested on Debian 11 (Bullseye).

A large number of settings and configurations can be found in defaults/main.yml.

None

- hosts: all
  become: yes
  become_method: sudo
  roles:
    - ansible-debian-11-hardening

The machine_hostname variable is created for consistency when no DNS record exists

inventory.ini

[servers]
192.168.0.11 ansible_ssh_user=admin machine_hostname=server01
192.168.0.12 ansible_ssh_user=admin machine_hostname=server02
192.168.0.13 ansible_ssh_user=admin machine_hostname=server03

inventory.yml

---
all:
  hosts:
    192.168.0.11:
    192.168.0.12:
    192.168.0.13:
  vars:
    ansible_ssh_user: admin
    machine_hostname: server01

• https://github.com/openstack/ansible-hardening
• https://madaidans-insecurities.github.io/guides/linux-hardening.html
• https://github.com/microsoft/MSTIC-Sysmon/tree/main/linux
• https://www.whonix.org/wiki/Hardened_Malloc
• https://github.com/threathunters-io/laurel
• https://wiki.archlinux.org/title/Security

GPL-3.0 License

This role was created by Dan Kir