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A risk framework is a guideline or recipe for how risk is to be assessed, resolved, and monitored. NIST established the Risk Management Framework (RMF) and the Cybersecurity Framework (CSF). These are both U.S. government guides for establishing and maintaining security, but the CSF is designed for critical infrastructure and commercial organizations, whereas the RMF establishes mandatory requirements for federal agencies. RMF was established in 2010, and the CSF was established in 2014.

The CSF is based on a framework core that consists of five functions: Identify, Protect, Detect, Respond, and Recover. The CSF is not a checklist or procedure—it is a prescription of operational activities that are to be performed on an ongoing basis for the support and improvement of security over time. The CSF is more of an improvement system rather than its own specific risk management process or security infrastructure.

The RMF, defined by NIST in SP 800-37 Rev. 2 (csrc.nist.gov/publications/detail/sp/800-37/rev-2/final), establishes mandatory security requirements for federal agencies. This is the primary risk framework referenced by the CISSP exam. The RMF has six cyclical phases (see Figure 2.5):

Prepare to execute the RMF from an organization- and system-level perspective by establishing a context and priorities for managing security and privacy risk.

Categorize the system and the information processed, stored, and transmitted by the system based on an analysis of the impact of loss.

Select an initial set of controls for the system and tailor the controls as needed to reduce risk to an acceptable level based on an assessment of risk.

Implement the controls and describe how the controls are employed within the system and its environment of operation.

Assess the controls to determine if the controls are implemented correctly, operating as intended, and producing the desired outcomes with respect to satisfying the security and privacy requirements.

Authorize the system or common controls based on a determination that the risk to organizational operations and assets, individuals, other organizations, and the nation is acceptable.

Monitor the system and the associated controls on an ongoing basis to include assessing control effectiveness, documenting changes to the system and environment of operation, conducting risk assessments and impact analyses, and reporting the security and privacy posture of the system.

[From NIST SP 800-37 Rev. 2]

FIGURE 2.5 The elements of the risk management framework (RMF) (from NIST SP 800-37 Rev. 2, Figure 2)

These six phases are to be performed in order and repeatedly throughout the life of the organization. RMF is intended as a risk management process to identify and respond to threats. Use of the RMF will result in the establishment of a security infrastructure and a process for ongoing improvement of the secured environment.

There is significantly more detail about RMF in the official NIST publication; we encourage you to review this publication in its entirety for a complete perspective on the RMF. Much of the information in the prior risk management sections in this chapter was derived from the RMF.

Another important guide to risk management is the ISO/IEC 31000 document “Risk management — Guidelines.” This is a high-level overview of the idea of risk management that many will benefit from reading. You can find it online at www.iso.org/obp/ui/#iso:std:iso:31000:ed-2:v1:en. This ISO guideline is intended to be useful to any type of organization, whether government or private sector. A companion guide, ISO/IEC 31004 “Risk management — Guidance for the implementation of ISO 31000” (www.iso.org/standard/56610.html) might also be of interest, along with ISO/IEC 27005, “Information technology — Security techniques — Information security risk management” (www.iso.org/standard/75281.html).

The NIST RMF is the primary focus of the CISSP exam, but you might want to review other risk management frameworks for use in the real world. Please consider the following for future research:

 The Committee of Sponsoring Organizations (COSO) of the Treadway Commission's Enterprise Risk Management — Integrated Framework

 ISACA's Risk IT Framework

 Operationally Critical Threat, Asset, and Vulnerability Evaluation (OCTAVE)

 Factor Analysis of Information Risk (FAIR)

 Threat Agent Risk Assessment (TARA)

For further research, you'll find a useful article here: www.csoonline.com/article/2125140/it-risk-assessment-frameworks-real-world-experience.html. Understanding that there are a number of well-recognized frameworks and that selecting one that fits your organization's requirements and style is important.