Everything you need to know about ISO/IEC 21827 (ANSSI) compliance

The ISO/IEC 21827 standard, also known as SSE-CMM (Systems Security Engineering Capability Maturity Model), responds to the challenges of cybersecurity in companies. Recognized by the ANSSI (French National Agency for the Security of Information Systems), it offers a clear reference framework for assessing and advancing the security of information systems. But what does this standard really encompass? Why comply? And how can this compliance be achieved in good conditions?

 

What is ISO/IEC 21827?

Published by ISO and IEC, ISO/IEC 21827 provides a framework for assessing the maturity of systems security engineering practices. It applies to both complex industrial systems and enterprise information systems.

This standard is based on a five-level maturity model and covers the entire lifecycle of security activities:

• Planning,
• Implementation,
• Follow-up,
• Continuous improvement.

ANSSI recognises this standard as relevant for assessing an organisation’s cybersecurity capabilities, particularly in sensitive or regulated sectors (health, finance, pharmaceuticals, etc.). It recommends its use to structure security approaches in the context of audits or compliance plans.

 

Why comply with ISO/IEC 21827?

Adopting this standard represents a strategic lever to strengthen the robustness of your information system. Here are the main benefits to be gained:

• Strengthen your cybersecurity posture : the standard helps identify your organization’s weaknesses in the face of cyber risks, structure your processes, and strengthen overall resilience.
  
• Structure internal practices : by establishing a clear framework, it facilitates the harmonization of security actions throughout the company.
  
• Comply with the expectations of the French authorities : in line with the recommendations of the ANSSI, it gives credibility to your approach with public and institutional actors.
  
• Facilitate audits and relations with partners : having a recognized reference system facilitates communication with stakeholders and reassures customers and suppliers alike.
  
• Better manage cyber investments : by measuring your level of maturity, you can precisely identify the levers to be prioritised.

 

How to successfully comply with the ISO/IEC 21827 standard?

ISO/IEC 21827 compliance requires a structured method and a strong involvement of IT, CISO and business teams.

Here are some key steps to manage this process:

1. Understand the ANSSI’s expectations

First and foremost, it is essential to analyse the ANSSI’s recommendations and align with its priorities: cybersecurity governance, risk management, supervision, incident management, etc. The ANSSI’s security requirements framework is a good starting point for framing your actions.

2. Carry out an internal diagnosis

This diagnosis allows us to identify your current level of maturity. It is based on interviews, documentary analyses, and an evaluation of practices on the following axes: governance, processes, skills, technologies, management.

The objective: to draw up a clear inventory, detect deviations from recommended good practices, and prioritize corrective actions.

3. Implement corrective actions

At the end of the diagnosis, a structured action plan must be launched: securing access, reviewing security policies, improving incident monitoring, strengthening internal skills, etc. All of these initiatives must be documented, piloted and reviewed regularly, in a continuous improvement approach.

4. Call on an interim manager to audit your compliance

To gain in efficiency and guarantee the objectivity of your approach, calling on an interim manager who is an expert in cybersecurity is a real added value.

WAYDEN provides you with experienced interim managers, capable of steering the entire project: from diagnosis to operational implementation, including training and strategic alignment.

At WAYDEN, our interim managers specialising in IT security have:

• 15 to 25 years’ experience in critical contexts.
• A perfect knowledge of ISO/IEC standards, SSE-CMM and ANSSI standards.
• A strategic external view to challenge your practices and build an operational roadmap.
• A rapid intervention capacity, in France and internationally, to secure your compliance project.

Would you like to carry out an ISO/IEC 21827 maturity audit or initiate another compliance process?

Contact us to find out more.