Threat modeling is a structured process with these objectives: identify security requirements, pinpoint security threats and potential vulnerabilities, quantify threat and vulnerability criticality, and prioritize remediation methods.
Done right, threat modeling provides a clear “line of sight” across a project that justifies security efforts. The threat model allows security decisions to be made rationally, with all the information on the table.
The threat modeling process naturally produces an assurance argument that can be used to explain and defend the security of an application. An assurance argument starts with a few high level claims, and justifies them with either subclaims or evidence.
When the development organization is serious about security, threat modeling is the most effective way to do the following:
• Detect problems early in the software development life cycle, even before coding begins.
• Spot design flaws that traditional testing methods and code reviews may overlook.
• Evaluate new forms of attack that you might not otherwise consider.
• Maximize testing budgets by helping target testing and code review.
• Identify security requirements.
• Remediate problems before software release and prevent costly recoding post-deployment.
• Think about threats beyond standard attacks to the security issues unique to your application.
• Keep frameworks ahead of the internal and external attackers relevant to your applications.
• Highlight assets, threat agents, and controls to deduce components that attackers will target.
• Model the location of threat agents, motivations, skills, and capabilities to locate potential attackers in relation to the system architecture.
1. Define the system: Identify the scope of the system, including its boundaries and interfaces with other systems.
2. Create a data flow diagram: Map out the flow of data through the system, including inputs, outputs, and processing steps.
3. Identify threats: Brainstorm potential threats that could exploit vulnerabilities in the system, such as data breaches, denial of service attacks, or unauthorized access.
4. Analyze threats: Assess the likelihood and impact of each identified threat, taking into account factors such as the system's architecture, technology, and environment.
5. Prioritize threats: Prioritize the most significant threats based on their potential impact and likelihood, and develop a plan to address them.
6. Implement controls: Develop and implement controls or countermeasures to mitigate the identified risks, such as firewalls, access controls, or encryption.
7. Test and verify: Test the system to verify that the implemented controls are effective in mitigating the identified risks.