20 Threat Modeling Interview Questions and Answers

Threat Modeling is the process of identifying potential security risks and vulnerabilities in a system. It is a critical part of the software development process, as it helps developers identify and mitigate potential security risks early on. When interviewing for a position that involves Threat Modeling, expect to be asked questions about your experience and approach to the process. In this article, we review some common Threat Modeling interview questions and provide guidance on how to answer them.

Threat Modeling Interview Questions and Answers

Here are 20 commonly asked Threat Modeling interview questions and answers to prepare you for your interview:

1. What is threat modeling?

Threat modeling is the process of identifying potential security threats to a system and then designing countermeasures to mitigate those threats. The goal of threat modeling is to make systems more secure by identifying and addressing potential security risks before they can be exploited.

2. Can you explain what STRIDE means in the context of threat modeling?

STRIDE is an acronym that stands for Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, and Elevation of Privilege. It is a mnemonic device used to help security professionals remember the six most common types of attacks.

3. Why do we need to use a framework like STRIDE while developing threat models?

STRIDE is a mnemonic acronym for the six most common types of attacks that can be carried out against a system: Spoofing, Tampering, Repudiation, Information disclosure, Denial of service, and Elevation of privilege. By using a framework like STRIDE, we can more easily identify potential threats and develop countermeasures to protect our systems.

4. How does DREAD differ from STRIDE?

DREAD is a threat modeling methodology that focuses on the potential damage that could be caused by a given threat, while STRIDE focuses on the different types of attacks that could be carried out. DREAD is therefore more focused on the potential consequences of an attack, while STRIDE is more focused on the different ways an attack could be carried out.

5. Can you explain the difference between software-only threats and external attacks?

Software-only threats are those that come from within the system itself, such as coding errors or malicious code that has been inserted into the system. External attacks, on the other hand, come from outside the system and can include things like denial of service attacks or social engineering.

6. If a developer were to try and design their own threat models, how would they go about it?

The first step would be to come up with a list of potential threats that could affect the system. Once the developer has a list of potential threats, they need to prioritize them in order of importance. After the threats have been prioritized, the developer can start working on designing countermeasures to mitigate the risks posed by each threat.

7. How does threat modeling help identify vulnerabilities in a system that may not be otherwise obvious?

Threat modeling helps to identify potential vulnerabilities in a system by identifying potential threats and then assessing the system’s ability to defend against those threats. By identifying potential vulnerabilities, threat modeling can help to prevent attacks before they happen.

8. What are some common types of threat scenarios for modern systems?

There are many different types of threat scenarios that can occur in modern systems, but some of the most common include:

– Denial of service attacks
– Malicious insiders
– Data breaches
– Identity theft
– Phishing attacks
– Advanced persistent threats

9. Do you think threat modeling should always be done before development begins or can it also be applied later on in the process?

I think that threat modeling can be done at different stages in the development process, depending on the needs of the project. If you are looking to identify potential security risks early on in the development process, then it makes sense to do threat modeling before development begins. However, if you are looking to identify risks that may have already been introduced during development, then threat modeling can also be applied later on in the process.

10. What is your opinion on using automated tools to perform threat modeling exercises?

I believe that automated tools can be helpful in performing threat modeling exercises, but they should not be relied on solely. I think it is important to have a human element involved in the process in order to ensure that all potential threats are considered.

11. In which situations might threat modeling prove ineffective as a security mechanism?

Threat modeling can be ineffective in situations where the potential threats are not known or where the system is too complex to accurately model. Additionally, if the system being modeled is constantly changing, threat modeling may not be able to keep up with the changes and could miss potential threats.

12. What is zero trust architecture?

Zero trust architecture is a security model that does not rely on predefined trust levels. In a zero trust system, every user and every device is treated as untrusted until it has been verified. This approach is designed to protect against insider threats and sophisticated attacks that can bypass traditional security measures.

13. Does threat modeling really add any value to a project?

Threat modeling can definitely add value to a project, as it can help identify potential security risks and vulnerabilities early on. However, it is important to keep in mind that threat modeling is not a perfect science, and there may be some risks that are not identified through this process. Ultimately, it is up to the project team to decide whether or not threat modeling is worth the time and effort.

14. What is an attack surface?

The attack surface of a system is the sum of the different points (the “surface”) where an unauthorized user (the “attacker”) can try to enter data into or extract data from the system.

15. When would you say that a threat model has been completed successfully?

A threat model is completed successfully when it has been able to identify all of the potential threats to a system and has provided mitigation strategies for each one. The goal is to make the system as secure as possible, and the threat model is a key part of that process.

16. Is it possible to re-use parts of a threat model for another similar project?

Yes, it is possible to re-use parts of a threat model for another similar project. However, it is important to note that the context of the new project may be different, and thus the threat model will need to be adapted to fit the new context. Additionally, the new project may have different requirements, which could also impact the threat model.

17. What is a false positive?

A false positive is when a security system incorrectly identifies a benign event as a threat.

18. What is the cost of detecting a vulnerability too late?

The cost of detecting a vulnerability too late can be significant. By the time a vulnerability is detected, the attacker may have already had time to exploit it and cause damage. Additionally, if the vulnerability is not detected until after it has been exploited, it may be more difficult to fix. Finally, if a vulnerability is not detected until it is too late, it may be more difficult to prevent future attacks.

19. How often should threat models be revisited?

There is no definitive answer to this question, as it will depend on the specific organization and the types of threats they face. However, it is generally recommended that threat models be revisited on a regular basis – at least annually, and preferably more often if possible. This allows organizations to keep their models up-to-date and relevant, and to adapt to new threats as they emerge.

20. What is a trusted computing base?

A trusted computing base (TCB) is a set of hardware, software, firmware, and processes that work together to create a secure environment. The TCB is the foundation upon which security features are built and is responsible for enforcing security policies. It is important to note that the TCB is not a security feature itself, but rather the foundation that security features are built upon.