How do you undertake threat modelling?

Threat modeling is a systematic process for identifying and assessing security threats and vulnerabilities in a system, application, or organization. It helps you proactively identify potential risks and take appropriate measures to mitigate them.

Here’s a step-by-step guide on how to undertake threat modeling:

1. Define the Scope:
   • Clearly define what you are threat modeling. It could be a specific application, a system, a network, or an entire organization.
2. Identify Assets:
   • List all the assets you want to protect. These could include data, hardware, software, intellectual property, personnel, and more.
3. Identify Threat Actors:
   • Identify potential threat actors or attackers who might target your assets. These could be internal (employees) or external (hackers, competitors, etc.).
4. Create a Data Flow Diagram:
   • Create a diagram that illustrates how data and information flow within your system or organization. This helps you understand the data’s journey and potential points of vulnerability.
5. Identify Threats:
   • Brainstorm and identify potential threats that could exploit vulnerabilities in your system. These threats can be categorized into:
     • Natural threats (e.g., earthquakes, floods)
     • Human threats (e.g., insider threats, social engineering)
     • Technology threats (e.g., malware, software vulnerabilities)
6. Assess Vulnerabilities:
   • Identify vulnerabilities in your system that could be exploited by the identified threats. Vulnerabilities could include weak passwords, unpatched software, misconfigured security settings, etc.
7. Determine the Likelihood and Impact:
   • Assess the likelihood of each threat occurring and the potential impact it would have on your organization. This helps prioritize which threats to address first.
8. Risk Assessment:
   • Calculate the risk associated with each threat by multiplying its likelihood by its impact. This provides a way to prioritize threats based on their risk level.
9. Develop Mitigation Strategies:
   • For high-risk threats, develop mitigation strategies to reduce the risk. These strategies could include implementing security controls, improving security awareness training, and enhancing incident response plans.
10. Validate Mitigations:
    • Test the effectiveness of the mitigation strategies to ensure they adequately reduce the risk. This may involve penetration testing, vulnerability scanning, and security audits.
11. Document and Review:
    • Document the threat model, including the identified threats, vulnerabilities, risk assessments, and mitigation strategies. Regularly review and update the threat model as your system or organization evolves.
12. Implement Continuous Monitoring:
    • Implement continuous monitoring to detect and respond to new threats and vulnerabilities as they emerge. This includes monitoring for security events, patch management, and keeping up-to-date with industry threat intelligence.
13. Educate and Train:
    • Educate and train your team members and employees about security best practices and the importance of threat modeling. An informed team is better equipped to respond to threats.

Threat modeling is an iterative process, and it should be an integral part of your organization’s security culture. Regularly revisiting and updating your threat model ensures that your defenses remain effective against evolving threats.