9 Methods for Calculating Cybersecurity Risk Scores: A Guide to Risk Analysis

Cyber risk scores measure the potential impact and likelihood of cyber threats. These scores help organizations prioritize their security efforts, allocate resources efficiently, and communicate risks to stakeholders clearly.

It’s important to note that while risk scoring is an integral part of risk management, it is not the same as a full risk assessment. Risk scoring is a component of the broader risk assessment process, which involves identifying, analyzing, and thoroughly evaluating risks. Essentially, risk scoring helps quantify or qualify risks. Whatever the method, it provides a basis for prioritizing actions.

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Methods for Calculating Cybersecurity Risk Scores

Various methods exist to calculate cybersecurity risk scores. Here, we’ll explore seven common methodologies and explain how each one works and the type of scores it produces.

1. Basic Risk Formula

The primary formula for calculating risk score is a straightforward equation. It involves multiplying the likelihood of a threat occurring by the potential impact of that threat:

Risk Score=Likelihood×Impact

This formula is straightforward and provides a quick way to assess risk. When it comes to a formula for calculating risk score in threat modelling, the equation gets more complex. But that’s for a different blog.

2. A Better Formula for Calculating Cyber Risk

The first method explained above is very simplistic. Here’s another commonly used formula, along with an explanation of how it’s calculated.

1. Threat Likelihood (TL): How likely is an attack? The more exposed your system, the higher the likelihood.
   
2. Vulnerability Severity (VS): How serious is the vulnerability? Is it an easy target or a hard one?
   
3. Impact Assessment (IA): What would the financial or reputational impact be if the attack occurred?
   

The Risk (R) is then calculated using this formula:
Risk = Threat Likelihood × Vulnerability Severity × Impact Assessment

3. FAIR (Factor Analysis of Information Risk)

FAIR is a more sophisticated approach that quantifies risk into monetary values, providing a detailed financial perspective on risk. FAIR divides risk into multiple components, including threat event frequency, vulnerability, and loss magnitude. The core concept of FAIR is to calculate the probable financial loss by considering these factors:

Risk=Probability of Threat Event×Vulnerability×Impact

By converting risk into financial terms, FAIR helps organizations understand the potential economic impact of cyber threats. This makes it easier to communicate risks to business stakeholders and prioritize mitigation strategies.

4. CVSS (Common Vulnerability Scoring System)

While not a direct risk-scoring method, CVSS is often used as a component in risk management frameworks. CVSS provides a numerical score (from 0 to 10) that represents the severity of a software vulnerability. This score can then be incorporated into broader risk calculations to assess the overall risk posed by specific vulnerabilities.

Is CVSS Considered a Risk Scoring Method?

CVSS primarily focuses on the severity of a given vulnerability and does not account for the likelihood of the vulnerability being exploited within a particular environment or an organization’s unique circumstances.

In contrast, a risk-scoring method measures both the likelihood and impact of a threat exploiting a vulnerability. It provides a holistic view of the risk by integrating various factors that influence both the probability of an attack and its potential consequences. Therefore, while CVSS is a valuable tool for assessing vulnerability severity, it is not a complete risk-scoring method. It does not provide the full picture needed for comprehensive risk management. The whole picture would need to include an understanding of how likely a threat is to exploit a vulnerability in a given context.

5. NIST SP 800-30

The NIST SP 800-30 framework offers a comprehensive approach to risk assessment, including a detailed methodology for calculating risk scores. The process involves:

1. Preparation: Define the scope of the risk assessment and establish a risk management strategy.
2. Threat Identification: Identify potential threats to the organization’s assets.
3. Vulnerability Identification: Determine vulnerabilities that could be exploited by the identified threats.
4. Impact Analysis: Evaluate the potential impact of successful threat exploitation.
5. Likelihood Determination: Assess the likelihood of threat occurrence and successful exploitation.
6. Risk Determination: Combine the results of the impact and likelihood analyses to calculate risk scores.
7. Control Recommendations: Recommend security controls to mitigate identified risks.
8. Documentation and Reporting: Document the findings and report them to stakeholders for informed decision-making.

The NIST framework is iterative, allowing for continuous improvement and refinement based on new information and changing conditions.

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

OCTAVE is a risk assessment methodology that emphasizes organizational context. It involves three phases: building asset-based threat profiles, identifying infrastructure vulnerabilities, and developing security strategies and plans. Risk scores are derived from the analysis of threats, vulnerabilities, and the impact on critical assets.

7. ISO/IEC 27005

ISO/IEC 27005 provides guidelines for information security risk management and is part of the ISO/IEC 27000 family of standards. The ISO method involves several steps:

1. Context Establishment: Define the risk management context, including the scope, boundaries, and risk criteria.
2. Risk Assessment: Identify risks, analyze them based on likelihood and impact, and evaluate the level of risk.
3. Risk Treatment: Develop and implement risk treatment plans to mitigate, transfer, or accept risks based on organizational objectives.

ISO/IEC 27005 uses a structured approach to assess and manage risks systematically, aligning with international best practices in information security management.

8. Centraleyes Approach

Centraleyes utilizes methodologies similar to the Loss Distribution Approach (LDA), commonly used in financial institutions. LDA estimates potential losses by analyzing historical data, industry benchmarks, and expert judgment. Centraleyes combines these assessments into an annual loss distribution, providing insights into potential financial impacts from cyber risks.

9. MITRE ATT&CK: Behavior-Based Context for Cyber Risk Scoring

While not a numeric scoring system, the MITRE ATT&CK® framework plays an increasingly important role in how organizations evaluate cyber risk—particularly in threat-informed and behavioral risk scoring models.

What It Is

MITRE ATT&CK is a publicly accessible, continuously updated framework that maps the tactics and techniques used by real-world adversaries. Rather than estimating the likelihood or impact of generic threats, it catalogs how specific actions are actually carried out, and which stages of an attack they belong to.

How It Fits into Risk Scoring

ATT&CK is not designed to produce a numeric score on its own. Instead, it provides a structured way to evaluate exposure and defensive coverage against known attacker behaviors. Organizations can use this framework to answer key risk questions such as:

• Are we monitoring for the techniques most commonly used against our industry?
• Do we have effective controls in place to detect or mitigate these techniques?
• Where are our visibility or detection gaps across the attack lifecycle?
  

By mapping known adversary techniques (from ATT&CK) to existing controls or gaps—and overlaying that with threat intelligence, critical asset mapping, and business context—security teams can derive a risk profile grounded in attacker behavior. This makes ATT&CK especially useful for organizations seeking qualitative or semi-quantitative insights into their cyber risk.

Strengths

• Real-world, adversary-aligned structure
• Helps prioritize risks by likely attacker behavior and coverage gaps
• Adaptable across cloud, enterprise, mobile, and ICS environments
  

Limitations

• Does not output a traditional numeric risk score
• Requires internal mapping and maturity to be operationally effective
• Best used as a supplement to other quantitative frameworks like FAIR or NIST 800-30
  

How to Calculate Risk Scores: A Practical Guide

Now that we’ve explored different methodologies, let’s walk through a practical example of calculating a risk score using the basic risk formula. Suppose you’re assessing the risk of a phishing attack on your organization.

1. Identify the Threat: Phishing attack.
2. Estimate the Likelihood: Based on historical data, you estimate a 30% chance of a phishing attack occurring within the next year.
3. Determine the Impact: If a phishing attack is successful, the potential impact is significant, with an estimated cost of $500,000 in damages.
4. Calculate the Risk Score: Using the basic risk formula:

Risk Score=Likelihood×Impact

Risk Score=0.3×500,000=150,000

This score provides a quantifiable measure of the potential risk, helping you prioritize your mitigation efforts.

Smart Shopping: What to Look Out For

With numerous cybers security solutions touting their ability to score risk, it’s crucial to be discerning. Here are some key considerations:

Over-Reliance on Automation

While automated risk-scoring solutions can save time and provide consistency, they should not replace human judgment. Automated tools may need the more contextual understanding that experienced professionals bring to the table. Buyers should ensure that any automated tool allows for human intervention and review.

Lack of Transparency

Some risk-scoring solutions use proprietary algorithms that are not fully transparent to users. This lack of transparency can be problematic as it prevents users from understanding how scores are calculated and whether the methodology aligns with their specific needs and risk landscape. Buyers should look for solutions that offer clear explanations of their scoring methodologies.

One-Size-Fits-All Approach

Risk environments vary significantly between industries, organizations, and even departments within the same organization. Solutions that offer a one-size-fits-all approach may not adequately address the unique risk factors and requirements of different entities. Buyers should seek solutions that are customizable and adaptable to their specific contexts.

Incomplete Data

Risk scoring is only as good as the data that feeds into it. Solutions that rely on incomplete or outdated data can produce misleading scores. Buyers should ensure that the solution integrates with their existing data sources and can incorporate real-time or near-real-time data updates.

Cost vs. Value

While cost is always a consideration, it should be weighed against the value provided by the solution. A lower-cost solution may lack critical features or scalability, while a higher-cost solution may offer more advanced capabilities that justify the investment. Buyers should carefully assess the cost-benefit ratio of each solution.

Compliance and Regulatory Considerations

Different industries have varying compliance and regulatory requirements. Buyers should ensure that the risk-scoring solution is compliant with relevant regulations and standards and that it helps facilitate compliance rather than creating additional challenges.

Scalability

As organizations grow and evolve, their risk management needs can change significantly. Buyers should ensure that the solution they choose is scalable and capable of adapting to future changes in the organization’s size, structure, and risk profile.

Emerging Trends and Future Directions in Cyber Risk Management

As the digital landscape continues to evolve, so do the methodologies and tools for cyber risk scoring. Here are some emerging trends worth knowing about:

1. Integration of AI and Machine Learning

Advanced AI and machine learning algorithms are being increasingly integrated into risk-scoring models to provide more accurate and dynamic assessments. These technologies can analyze vast amounts of data in real-time, identifying patterns and predicting potential threats more effectively than traditional methods.

2. Real-Time Risk Monitoring

The shift towards continuous monitoring and real-time risk assessment allows organizations to respond promptly to emerging threats. This proactive approach enhances an organization’s ability to mitigate risks before they materialize into significant issues.

3. Industry-Specific Risk Models

Developing risk-scoring models tailored to specific industries can provide more relevant and accurate risk assessments. For example, healthcare organizations might focus on risks related to patient data breaches, while financial institutions might prioritize fraud and financial theft risks.

4. Enhanced Collaboration and Information Sharing

Increased collaboration and information sharing among organizations, industry groups, and government agencies can lead to better risk assessment and management practices. Sharing threat intelligence and best practices can help organizations stay ahead of cyber threats.

5. Regulatory Developments and Compliance

As regulatory requirements evolve, so too must risk scoring methodologies. Keeping abreast of changes in regulations and standards ensures that risk assessments remain compliant and relevant.

6. Human Factor Consideration

Incorporating human factors into risk scoring, such as employee behavior and insider threats, provides a more comprehensive view of organizational risk. Understanding the human element can help in developing targeted training and awareness programs to mitigate these risks.

Final Word on Cybersecurity Risk Scores

Let your cyber risk scores guide your path to resilience. Use them to prioritize actions, strengthen defenses, and protect your organization in an ever-changing digital landscape.

Key Takeaways

1. Cyber Risk Scoring Helps You Prioritize

Cyber risk scoring quantifies risks by assessing likelihood and impact, helping you focus on the most critical areas like customer data or public-facing systems.

2. Start with What’s Most Important

 Identify your most valuable assets to prioritize protection:

• Critical services (e.g., customer-facing platforms)
• Sensitive data (e.g., PII, payment details)
• Public-facing systems (e.g., websites)
  

3. Assess Likelihood and Impact

Combine likelihood (how likely an attack is) and impact (financial and operational consequences) to calculate your risk score and identify urgent threats.

4. Understand Asset Value

Know the value of each asset to prioritize:

• Operational importance
• Data sensitivity
• Replacement costs
  

5. Compensating Controls Lower Risk

Implement compensating controls (firewalls, encryption) to reduce the likelihood and impact of risks and make your score more accurate.