What Is Threat Modeling?

Threat modeling is the process of using hypothetical scenarios, system diagrams, and testing to help secure systems and data. By identifying vulnerabilities, helping with risk assessment, and suggesting corrective action, threat modeling helps improve cybersecurity and trust in key business systems.

Why is threat modeling necessary?

As organizations become more digital and cloud-based, IT systems face increased risk and vulnerability. Growing use of mobile and Internet of Things (IoT) devices also expands the threat landscape. And while hacking and distributed-denial-of-service (DDoS) attacks repeatedly make headlines, threats can also come from within--from employees trying to steal or manipulate data, for example.

Smaller enterprises are not immune to attacks either--in fact they may be more at risk because they don't have adequate cybersecurity measures in place. Malicious hackers and other bad actors make risk assessments of their own and look for easy targets.

What are the benefits of threat modeling?

The process of threat modeling can:

  • Provide an enhanced view of systems. The steps involved in threat modeling--creating data flow diagrams (DFDs) and graphical representations of attack paths, as well as prioritizing assets and risks--help IT teams gain a deeper understanding of network security and architecture.
  • Help enable better collaboration on security. Proper threat modeling requires input from many stakeholders. Participating in the process can help instill cybersecurity consciousness as a core competency for all participants.
  • Facilitate risk prioritization. Businesses can use the threat data provided by modeling to make decisions about which security risks to prioritize--a helpful process for understanding where to allocate people and budget resources.

Does threat modeling require special software?

While basic threat modeling can be performed in a brainstorming session, larger enterprises with more potential vulnerabilities can use software and hardware tools to improve the security of complex systems with multiple points of entry. Software helps provide a framework for managing the process of threat modeling and the data it produces. It can also help with risk and vulnerability assessment and suggest remediation.

What is involved in the threat modeling process?

Steps involved in threat modeling include:

  • Identify assets. An asset could be account data, intellectual property, or simply the reliable functioning of a system.
  • Diagram the system. DFDs provide a high-level, asset-centric view of systems and the data flows of attacks. An attack tree, or graphic representation of an attack path, illustrates the possible origins and paths of attacks.
  • Analyze threats. Use threat modeling methods to further analyze specific threat types, identify potential threats, map data flows, and quantify risk.
  • Perform risk management and prioritization. Many threat modeling tools produce threat scores and data for calculating risk. Stakeholder input is essential to this step.
  • Identify fixes. Once you identify the areas, assets, or threats that matter most to the organization, the next steps may be apparent. Changing firewall, encryption, or multi-factor authentication settings are examples of steps to address a threat.

How do I measure the effectiveness of threat modeling?

Two ways to measure effectiveness are:

  • Common Vulnerability Scoring System (CVSS). CVSS produces standardized scores for application vulnerabilities, IT systems and elements, and IoT devices; the scores can be calculated with a free online tool. For additional perspective, scores can be compared against a database of existing scores crowdsourced from similar enterprises.
  • Penetration testing. Sometimes referred to as "ethical hacking," penetration testing is the process of staging dummy attacks on a system to measure its strengths and weaknesses. Pen tests may require a good deal of time-consuming data analysis, so organizations should be wary of running too many tests, or tests on assets that are not sufficiently high-risk to justify the cost.
  • Is threat modeling available as a service?

    Yes. Threat modeling as a service (TMaaS) can allow an organization to focus on remediation and high-level network architecture decisions, while leaving necessary data-crunching to TMaaS providers. TMaaS also can perform continuous threat modeling, automatically running testing anytime a system is updated, expanded, or changed. TMaaS solutions incorporate threat intelligence--such as data about threats and attacks crowdsourced from organizations worldwide--that can inform threat hypotheses for networks and improve network security.

Threat modeling methods and tools

CIA method

As a starting point, use the CIA (confidentiality, integrity, availability) method to define what needs protecting in the organization. For example, there may be sensitive customer information (confidentiality), company operational or proprietary data (integrity), or reliability of a service such as a web portal (availability).

Attack trees

Attack trees are a graphic representation of systems and possible vulnerabilities. The trunk of the attack tree is the asset, while entry points and threats are branches or roots. Attack trees are often combined with other methods.


Developed by Microsoft, STRIDE (spoofing, tampering, repudiation, information disclosure, denial of service, elevation of privilege) is one of the oldest and most widely used frameworks for threat modeling. STRIDE is a free tool that will produce DFDs and analyze threats.


PASTA (process for attack simulation and threat analysis) is a framework designed to elevate threat modeling to the strategic level, with input from all stakeholders, not just IT or security teams. PASTA is a seven-step process that begins with defining objectives and scope. It includes vulnerability checks, weakness analysis, and attack modeling, and ends with risk and impact analysis expressed through scoring.


An open-source tool available as a spreadsheet template or stand-alone program, Trike consists of a matrix combining assets, actors, actions, and rules. When parameters and data are entered in this matrix, the program produces a score-based analysis of risks and probabilities.


VAST (visual, agile, and simple threat) modeling consists of methods and processes that can be easily scaled and adapted to any scope or part of an organization. The results produce benchmarks that can be used to make reliable comparisons and measurements of effective risk across a whole organization.

Persona non grata

This method is similar to criminal profiling in law enforcement. To anticipate attacks in more detail, brainstorming exercises are performed to create a detailed picture of a hypothetical attacker, including their psychology, motivations, goals, and capabilities.


The LINDDUN framework focuses on analysis of privacy threats, based on the categories that form its acronym: linkability, identifiability, non-repudiation, detectability, disclosure of information, unawareness, and non-compliance. It uses threat trees to help users choose the relevant privacy controls to apply.