Automating CIS Benchmark Compliance on RHEL 9 Using Ansible | RedHat AAP or AWX

Security compliance is no longer optional—especially in regulated industries like BFSI. Organizations are expected to adhere to well-defined benchmarks such as the Center for Internet Security (CIS) standards to ensure hardened and secure systems.

In this blog, we’ll explore how to automate CIS Benchmark enforcement on RHEL 9 using Ansible, making compliance repeatable, auditable, and scalable.

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Why CIS Benchmarking Matters

CIS benchmarks provide:

• Industry-recognized security standards
• Hardened configurations for OS and applications
• Reduced attack surface
• Compliance alignment (PCI-DSS, ISO 27001, etc.)

Manual implementation is complex and error-prone—automation solves that.

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Playbook Overview

This playbook performs:

1. GRUB password hardening
2. User account preparation
3. CIS role execution (Level 1 Server profile)
4. Audit and compliance validation

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Key Components Explained

1. Secure Bootloader Configuration (GRUB Hardening)

One of the critical CIS controls is protecting bootloader settings to prevent unauthorized changes.

This playbook:

• Uses expect to automate interactive password setup
• Sets a GRUB2 password securely
• Updates GRUB configuration

grub2-setpassword

🔐 Why it matters:
Prevents attackers from modifying boot parameters (e.g., entering single-user mode).

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2. Secure Password Handling

The playbook uses:

no_log: true

This ensures:

• Passwords are not exposed in logs
• Sensitive data remains protected

⚠️ Best Practice:
Use Ansible Vault instead of plain text passwords.

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3. User Management

The playbook:

• Gathers existing users
• Sets password for the automation user

password_hash('sha512')

🔐 This aligns with secure password storage practices.

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4. CIS Role Execution

The core of the automation is the RHEL9-CIS role, which enforces multiple controls:

• File permissions
• SSH hardening
• Audit configuration
• Kernel parameters
• Logging and monitoring

Key configurations:

• setup_audit: true → Enables auditd setup
• run_audit: true → Runs compliance checks
• skip_reboot: false → Allows required reboots

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5. Compliance Validation with Goss

The playbook integrates Goss for validation:

• Lightweight validation tool
• Ensures system state matches expectations
• Provides quick compliance feedback

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Execution Flow

Install Dependencies → Set GRUB Password → Update Config
→ Gather Users → Apply CIS Role → Run Audit → Validate Compliance

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Security Considerations

✅ Handled Well

• Sensitive data masked (no_log)
• Idempotent execution
• Automated audit validation

⚠️ Needs Improvement

• Avoid hardcoded passwords (primod123)
• Use Ansible Vault for secrets
• Validate impact before enabling reboot

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Best Practices for Production

• Run in audit-only mode first:

  audit_only: true
  

• Test in staging before production rollout
• Maintain exception list for business-critical users
• Integrate with SIEM tools for reporting
• Schedule periodic compliance scans

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Use Cases in Enterprise Environments

• BFSI compliance enforcement
• Cloud VM hardening (AWS, Azure, etc.)
• Regulatory audits
• Secure baseline creation

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Benefits of This Approach

🚀 Automation at Scale

Apply CIS policies across hundreds of servers consistently.

🔁 Repeatability

Same configuration every time—no drift.

📊 Audit-Ready

Reports and validation built-in.

🔒 Improved Security Posture

Reduced vulnerabilities and misconfigurations.

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Potential Enhancements

• Integrate with **Red Hat Ansible Automation Platform workflows
• Add approval gates (ServiceNow/Jira)
• Enable Event-Driven Automation (EDA)
• Centralized reporting dashboards
• Role-based execution (Level 1 vs Level 2 CIS)

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Conclusion

Automating CIS benchmark enforcement transforms security from a manual task into a continuous, reliable process. With Ansible, organizations can ensure systems remain compliant, secure, and audit-ready at all times.

This playbook is a strong foundation for building a compliance-as-code strategy, enabling proactive security management across your infrastructure.

This is a playbook which i have use to benchmark my server its score is around 91.00%

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- name: CIS Benchmark mapping

hosts: all

become: true

vars:

# It is strongly recommended to store this in an Ansible Vault

grub_password: "YourSecurePasswordHere"

pre_tasks:

- name: Ensure the expect package is installed

ansible.builtin.package:

name: expect

state: present

- name: Set GRUB2 password for the root user

ansible.builtin.expect:

command: grub2-setpassword

responses:

'Enter password:': "{{ grub_password }}"

'Confirm password:': "{{ grub_password }}"

# Only run if the user configuration doesn't already exist

creates: /boot/grub2/user.cfg

register: grub_pw_set

no_log: true # Prevents the password from appearing in logs

- name: Update GRUB2 configuration

ansible.builtin.command:

cmd: grub2-mkconfig -o /boot/grub2/grub.cfg

when: grub_pw_set.changed

- name: Gather available local users

ansible.builtin.getent:

database: passwd

register: user_facts

# - name: "Setup Password for ec2-user"

# ansible.builtin.user:

# name: ec2-user

# password: "{{ 'primod123' | password_hash('sha512') }}"

# when: "'ec2-user' in user_facts"

# - name: "Setting password"

# ansible.builtin.debug:

# msg: "Password for ec2-user has been set. Please change it after first login."

# when: "'ec2-user' in user_facts"

# - name: "Setup Password for azureuser"

# ansible.builtin.user:

# name: azureuser

# password: "{{ 'primod123' | password_hash('sha512') }}"

# when: "'azureuser' in user_facts"

# - name: "Setting password"

# ansible.builtin.debug:

# msg: "Password for azureuser has been set. Please change it after first login."

# when: "'azureuser' in user_facts"

- name: "Setup password for ansible_user"

ansible.builtin.user:

name: "{{ ansible_user }}"

password: "{{ 'primod123' | password_hash('sha512') }}"

#when: "'{{ ansible_user }}' in user_facts"

roles:

- name: "RHEL9-CIS"

vars:

setup_audit: true

run_audit: true

# audit_only: true

rhel9cis_allow_authselect_updates: false

rhel9cis_crypto_policy_ansiblemanaged: false

skip_reboot: false

rhel9cis_warning_banner: |

'This Policy is Applied on RHEL9-CIS Benchmark.

Unauthorized access to this system is prohibited.

All activities on this system are logged and monitored.

By accessing this system, you consent to such monitoring and logging.

By Anible Automation Platform Team

Automation Engineering Team

for any new changes please reach out to us.'

rhel9cis_sudoers_exclude_nopasswd_list:

- "{{ ansible_user }}"

goss_url: https://github.com/goss-org/goss/releases/download/v0.4.9/goss-linux-arm64

goss_version:

release: v0.4.9

checksum: "sha256:87dd36cfa1b8b50554e6e2ca29168272e26755b19ba5438341f7c66b36decc19"

tags:

- level1-server