Threat modeling used to be something done once during the design phase and then usually forgotten about. But now, software and security industries have realized it needs to be an ongoing part of a developer’s workflow—even if they’re really busy with new features and bug fixes.
As we well know, even a single vulnerability in code can lead to serious and costly data breaches. That’s why the Open Source Foundation for Application Security (OWASP) believes threat modeling is “best applied continuously throughout a software development project (SDLC).”
What Is Threat Modeling?
Threat modeling can help developers identify, evaluate, and mitigate potential security threats throughout the SDLC. Using threat modeling early and continuously means developers can protect applications from attacks while building functionality.
At its core, threat modeling is about answering a few key questions:
-
What could go wrong with this feature/system?
-
How bad would it be if it did?
-
How do we stop it (or at least make it harder for bad actors)?
Integrating Threat Modeling into Agile Development
Integrating threat modeling into the development process doesn’t have to be a huge hassle; it’s about making security a natural part of the workflow. Developers who work in an agile environment like Scrum can incorporate continuous threat modeling into development processes in a way that’s easy and scalable. Here’s how:
1. Identify Critical Assets Early
Firstly, developers need to figure out what the most critical assets are in the application they’re working on, such as sensitive user data or financial information. Once that’s done, they need to think about potential threats that could affect these, such as unauthorized access, data breaches, or tampering.
2. Think Like an Attacker with Abuser Stories
Abuser stories are an essential part of threat modeling. What are they? Abuser stories focus on how attackers could cause harm, steal data, or disrupt services. Rather than just thinking about how users will interact with an application, developers need to understand how attackers might exploit it. For example:
“As an attacker, I want to gain unauthorized access to company data by manipulating user input in the search bar.”
Creating stories can help developers prepare for attacks by identifying specific vulnerabilities for each feature.
3. Prioritize Threats Based on Impact
Not all threats are the same when it comes to impact. Some may be highly likely to happen, while others may be less probable but more disastrous. Developers can use a risk assessment model, like DREAD (Damage, Reproducibility, Exploitability, Affected users, Discoverability), to order threats based on their potential impact. It helps make sure that the most critical vulnerabilities are addressed first.
4. Embed Security in Every Sprint
In agile development, threat modeling should fit neatly into sprint cycles:
-
Backlog Refinement
As developers work through the product backlog, they should assess each feature for potential security risks. -
Sprint Planning
When it comes to sprint planning, prioritize the security risks found during backlog refinement. Focus on the biggest vulnerabilities and add mitigation strategies to sprint tasks. -
Sprint Review and Retrospective
After each sprint, developers should go over the identified security threats. For example, did the mitigation strategies work as they should have? Were any new risks discovered during development? This way, the threat modeling process can be adjusted if needed.
Integrating threat modeling into each phase of the development process ensures applications stay protected as they progress.
Tips for Effective Continuous Threat Modeling
Start Small and Scale Up
Developers can start by creating one or two abuser stories per sprint. As teams become more comfortable with the process, gradually increase the number of stories addressed.
Use Automation
Incorporate an automated threat modeling solution in your development process to generate abuse stories and identify threats automatically. Detecting risks early on makes it easier to maintain secure code throughout the sprint.
Designate Security Champions
Threat modeling is something that should be collaborative. Relying solely on the security team isn’t scalable, as they can’t handle every security risk as a company grows. That’s why it’s preferable to choose security champions from other teams who can provide advice and help protect critical assets.
The Benefits of Continuous Threat Modeling
Here’s how integrating threat modeling can help your team and business:
Staying Ahead of Security Issues
Staying ahead of security issues is probably the main advantage of continuous threat modeling. If developers find threats right at the start of the software development process, it reduces the chance of vulnerabilities getting into production. Being proactive lessens the risk of security breaches and the high costs that come with them.
Creating a Culture of Security
Continuous threat modeling also brings about a culture of security within development teams. When security becomes a regular part of the workflow, developers are more likely to write secure code, and stakeholders are more confident that the application is being developed with security in mind.
Protecting Your Reputation and Building Trust
Security breaches can damage an organization’s reputation, so by using continuous threat modeling and adding it into every sprint, it’s possible to help build trust with users. Having a high level of security at every step is vital for customer confidence.
Simplify Threat Modeling for Developers with SecureFlag
Security doesn’t have to slow developers down. Integrating continuous threat modeling into the agile process can resolve potential risks without stopping feature development. It’s about making security part of the workflow and something that’s always thought about, not just at the start or finish of a project.
ThreatCanvas, our automated threat modeling tool, makes threat modeling so much easier with its visual, collaborative platform. Developers can map out threats, spot vulnerabilities, and mitigate them early—plus many more features!
On top of that, SecureFlag has you covered when it comes to coding securely. We deliver hands-on training in virtual labs to help developers code securely from the very beginning.
