For our first 2025 Mike Drop, we are looking at the differences between ISO 27001:2022, NIST SP 800-171, and CMMC.

In today’s cybersecurity landscape, organizations handling sensitive information must comply with various security frameworks and standards. Three of the most commonly referenced standards are ISO 27001, NIST SP 800-171, and CMMC. While they share similarities in their goal of securing information, their scope, implementation, and certification processes differ significantly. Understanding these differences is key to determining which framework best fits your organization’s needs.

ISO 27001: The Global Information Security Standard

ISO 27001 is an internationally recognized standard for establishing, implementing, maintaining, and continually improving an Information Security Management System (ISMS). It provides a risk-based approach to information security, allowing organizations to implement security controls based on their unique risks and business context.

• Scope: Broadly applicable to organizations of all sizes and industries.
• Approach: Focuses on risk management and continuous improvement.
• Certification: Requires an independent audit to achieve formal certification.
• Who Needs It? Companies seeking a globally recognized standard for managing information security risks, regardless of industry.

NIST SP 800-171: Protecting Controlled Unclassified Information (CUI)

NIST Special Publication 800-171 is a set of security requirements developed by the National Institute of Standards and Technology (NIST) to protect Controlled Unclassified Information (CUI) in non-federal systems and organizations. It is primarily used by U.S. government contractors.

• Scope: Applies to organizations handling CUI in non-federal systems.
• Approach: Provides 110 specific security requirements across 14 control families.
• Certification: Compliance is typically self-attested or assessed contractually.
• Who Needs It? U.S. government contractors and subcontractors who handle CUI.

CMMC: Strengthening Cybersecurity for Defense Contractors

The Cybersecurity Maturity Model Certification (CMMC) was introduced by the U.S. Department of Defense (DoD) to enforce stricter cybersecurity measures for defense contractors. CMMC builds upon NIST SP 800-171, incorporating additional security practices and a maturity model.

• Scope: Specifically designed for companies in the Defense Industrial Base (DIB).
• Approach: Implements a tiered maturity model with different levels of cybersecurity readiness.
• Certification: Requires third-party audits and certification based on an organization’s required maturity level.
• Who Needs It? Any organization doing business with the DoD, including subcontractors.

Key Differences at a Glance

Feature	ISO 27001	NIST SP 800-171	CMMC
Focus	Information Security Management	Protecting CUI in non-federal systems	Cybersecurity for Defense Contractors
Applicability	Any organization worldwide	U.S. government contractors handling CUI	U.S. defense contractors
Certification	Requires independent audit	Self-attestation (or contractually required assessment)	Third-party certification required
Flexibility	Risk-based, adaptable	Fixed security controls	Tiered model with increasing requirements

Which One Is Right for Your Organization?

• If your organization wants a globally recognized approach to information security management, ISO 27001 is the best fit.
• If your company handles Controlled Unclassified Information (CUI) for the U.S. government, you need to comply with NIST SP 800-171.
• If you are part of the Defense Industrial Base (DIB) and contract with the DoD, you must achieve CMMC certification at the required level.

Conclusion

Each of these frameworks serves a unique purpose, but all aim to improve cybersecurity and safeguard sensitive information. Understanding the distinctions between ISO 27001, NIST SP 800-171, and CMMC ensures that your organization selects the right framework for compliance and security. If you need guidance on implementing these standards, contact Systems Certification Body (SCB) for expert assistance in navigating compliance and certification processes.

Need help with compliance or certification? Reach out to us today to learn how we can support your certification journey!