The Difference Between ISO/IEC 27001 and NIST CSF

Emad Shahidi
April 12, 2021


Two of the most well-known cybersecurity frameworks are the International Organisation for Standardisation’s ISO/IEC 27001 and the National Institute of Standards and Technology’s Cyber Security Framework (NIST CSF). Both ISO/IEC 27001 and NIST CSF involve establishing a risk management framework and implementing information security controls. However, the benefits derived from the different standards vary in terms of how they approach information security. In this article, we’ll compare the two in order to help you decide which one is more suitable for your company.


ISO/IEC 27001 and NIST CSF are cybersecurity frameworks that offer similar control measures to tackle information security and risk management. They are reasonably easy to implement either separately or in conjunction with each other, especially as they share a number of common principles which are mapped across. However, while they both deliver a continual improvement process and use a risk-based approach, they tackle information security from different angles.

ISO/IEC 27001:

The primary aim of the ISO/IEC 27001 framework is to give guidance to businesses on how to establish, implement, maintain and improve their Information Security Management System (ISMS). The framework is less technical than the NIST CSF framework with an emphasis on providing best practice recommendations for risk-based management. There are ten clauses that guide organisations through their Management System, risk assessment, and risk treatment plan to ensure adequate controls are in place. Furthermore, there is a catalogue of 114 security controls grouped in 14 domains which business are advised to implement based on their risk assessment. These controls are more expanded in the ISO/IEC 27002 which complements the ISO/IEC 27001.

One of the biggest advantages of ISO/IEC 27001 is its verifiability by an independent third-party organisation, also known as a Certification Body. The fact that businesses are awarded a certificate of compliance that is internationally recognised is a massive bonus.


The NIST cybersecurity framework was initially created to help US federal agencies to manage risk. Although it was developed for critical infrastructure sectors, it has since been adapted for organisations across all industries and outside the US. The framework is ideally suited to any company that is heavily reliant on technology, although the flexible framework can accommodate anything from standard information systems to the Internet of Things. The framework is governed by five overarching functions: Identify, Protect, Detect, Respond, and Recover. Each of these functions is graded on a scale of 0-4, which helps organisations to build their cybersecurity maturity. This rating system and the well-defined flow of security functions are beneficial as it helps board directors and senior management to understand and appreciate positive developments in a risk improvement program. However, the downside of the framework is that it is difficult to prove compliance, as there is no formal certification for NIST CSF.

ISO/IEC 27002 AND NIST 800-53 REV. 5

The ISO/IEC 27002 and NIST 800-53 Rev. 5 standards are the next level of security best practices that offer more robust coverage on the security controls than the cybersecurity frameworks we’ve covered so far. These two standards offer a comprehensive catalogue of controls that an organisation can choose from. Whilst ISO/IEC 27001 and 27002 work hand in hand, a lot of organisations rely on their service providers and technology partners to meet the intent and rigour of the controls. Comparably, whilst, NIST CSF cross-references to controls found in both ISO 27001 and NIST 800-53 Rev. 5, organisations tend to hinge on their vendors to satisfy the intent and rigour of the controls. These two frameworks cover the same fundamental information security controls framework but differ in content and layout.

ISO/IEC 27002:

ISO/IEC 27002 contains 14 subsections of security controls that work as supporting documentation to aid the implementation of ISO/IEC 27001. Ultimately, as the framework provides the specifications for controls required to implement ISO/IEC 27001, it is vital in order to achieve certification. ISO/IEC 27002 contains the finer details and best practices required to build a comprehensive IT security system. Its key benefit is its international recognition and the fact that it provides coverage for many common requirements and compliance regulations. However, it’s worth noting that ISO charges for its publication.

NIST 800-53 Rev 5:

NIST 800-53 Rev. 5 contains twenty groups of security controls, which overlaps with the 14 domains of controls found in ISO/IEC 27002. As mentioned for NIST CSF, the framework was designed to protect the US federal government. However, it can be applied to many industries and is commonly used in financial, medical and government contracting industries. One of the benefits of NIST 800-53 Rev. 5 is that it is a superset of ISO/IEC 27002 containing all its components as well as other requirements. It’s also worth noting that, in contrast to ISO, all documentation is freely available.


To be able to choose which framework will be best for your business, you need to consider your business environment (i.e. the risk landscape) and your business requirements (i.e. the risk appetite). The best framework for your organisation will depend on which industry you are in, your customers’ requirement, applicable regulatory obligations, available resources, and organisational priorities. Moreover, there might be an overriding outside pressure from clients and governing or regulatory bodies to comply with a specific standard. Both ISO and NIST standards are well-designed and established ways to uplift your level of cybersecurity maturity and manage risk. However, as they tackle information security and risk management from different angles, one may be more suitable than another. At Infotrust, we have helped guide many companies through both the ISO and NIST frameworks and can help you to decide which standard you should comply with. To find out more about the security consulting services we offer, download our datasheet.

This completes our 3-part blog series on cyber security frameworks. We hope you have a better understanding of the two cyber security frameworks and which one is more appropriate for your business. If you’d like to know more information on NIST CSF, click here. If you’d like to read why you should be ISO certified, click here.