Introduction

ISO 27000 is a family of standards focused on information security management systems (ISMS). Within this series, some standards are normative, meaning they define essential requirements, while others are informative, providing guidelines and recommendations.

Difference Between Normative and Informative Standards

  • Normative standards are mandatory for certification and compliance.
    They establish requirements that organizations must follow to achieve ISO certification.
  • Informative standards provide guidance and best practices but are not required for certification. They help organizations understand and implement security measures effectively.

Among the ISO 27000 series, ISO 27001, ISO 27006, and ISO 27009 are normative, making them crucial for compliance and certification. This blog post will explain each of these in detail and provide an overview of the informative standards in the series.

Normative ISO Standards in the 27000 Series

ISO 27001: The Foundation of ISMS

ISO 27001 is the core standard in the ISO 27000 series, specifying requirements for establishing, implementing, maintaining, and continually improving an ISMS. It provides a risk-based approach to information security, requiring organizations to:

  • Define a risk management process
  • Establish policies and objectives for information security
  • Implement controls from Annex A (which maps to ISO 27002)
  • Monitor, review, and improve the ISMS continually

Organizations that comply with ISO 27001 can achieve certification, demonstrating their commitment to managing information security risks effectively.

ISO 27006: Requirements for Certification Bodies

ISO 27006 sets the requirements for certification bodies that audit and certify organizations for ISO 27001 compliance. It ensures that auditors follow consistent and high-quality assessment methodologies. The key aspects of ISO 27006 include:

  • Accreditation requirements for certification bodies
  • Competency criteria for ISMS auditors
  • Audit process and procedures
  • Reporting and impartiality principles

By adhering to ISO 27006, certification bodies maintain credibility and ensure that ISO 27001 certifications are valid and trustworthy.

ISO 27009: Sector-Specific Adaptations of ISO 27001

ISO 27009 provides guidance on adapting ISO 27001 for specific industries or sectors. It allows the development of sector-specific information security standards while maintaining alignment with the ISO 27001 framework.

This standard is particularly useful for industries with unique regulatory and operational security requirements, such as healthcare, finance, and telecommunications. It ensures that sector-specific standards remain compatible with ISO 27001 while addressing industry-specific risks.

Informative ISO Standards in the 27000 Series

Unlike the normative standards, the following standards provide guidance rather than mandatory requirements:

ISO 27000: Overview and Vocabulary

ISO 27000 defines key terms and concepts used across the ISO 27000 series. It serves as a reference point for understanding information security principles and the structure of ISMS standards.

ISO 27002: Information Security Controls

ISO 27002 provides detailed guidance on implementing the security controls outlined in Annex A of ISO 27001. It covers best practices for:

  • Access control
  • Cryptography
  • Physical security
  • Incident management

Although not a certification standard, ISO 27002 helps organizations strengthen their ISMS controls.

ISO 27003: ISMS Implementation Guidance

ISO 27003 offers guidance on implementing an ISMS based on ISO 27001. It covers:

  • Project planning
  • Risk assessment methodologies
  • ISMS documentation requirements
  • Stakeholder engagement

ISO 27004: ISMS Monitoring and Measurement

ISO 27004 provides guidelines on how to measure and evaluate the effectiveness of an ISMS. It includes:

  • Metrics for assessing security performance
  • Continuous improvement techniques
  • Compliance monitoring strategies

ISO 27005: Risk Management for Information Security

ISO 27005 offers a structured approach to risk management in ISMS, aligning with ISO 27001’s risk-based approach. It guides organizations in:

  • Identifying and assessing security risks
  • Selecting appropriate mitigation strategies
  • Implementing a continuous risk management process

ISO 27007: Guidelines for ISMS Audits

ISO 27007 complements ISO 27006 by providing best practices for conducting ISMS audits. It helps organizations prepare for ISO 27001 certification audits and maintain compliance.

ISO 27008: Security Controls Assessment

ISO 27008 offers guidance on assessing the effectiveness of information security controls. It helps organizations verify whether implemented controls meet their security objectives.

ISO 27010 to ISO 27099: Industry-Specific and Emerging Standards

The ISO 27000 series continues to evolve with additional standards covering:

  • Information security in inter-organizational communication (ISO 27010)
  • Cloud security (ISO 27017, ISO 27018)
  • Privacy management (ISO 27701)
  • Cybersecurity frameworks (ISO 27032)

Conclusion

ISO 27001, ISO 27006, and ISO 27009 are the key normative standards that define requirements for ISMS implementation, certification, and sector-specific adaptations. The rest of the ISO 27000 series provides informative guidance, helping organizations understand, implement, and improve their ISMS. Understanding these distinctions ensures organizations can effectively navigate compliance, certification, and best practices for information security management.

By following these standards, businesses can strengthen their cybersecurity posture, protect sensitive data, and demonstrate their commitment to information security best practices.