Looking for the best in DAST: How to select DAST tools for DevSecOps

DAST is a natural match for DevOps workflows, but picking the right tool for your teams and your organization can get confusing. Will any vulnerability scanner work? Does it replace your SAST? Will it drown your developers in false positives? Here’s a quick guide to evaluating DAST products when building a DevSecOps process.

Looking for the best in DAST: How to select DAST tools for DevSecOps

Web application security testing tools come in a variety of flavors depending on what you’re testing and how, but for a holistic look at the security status of your running apps, dynamic application security testing (DAST) is the way to go. Designed to test websites and applications by mimicking real attacks and locating runtime security flaws from the outside, DAST provides an invaluable look at how malicious actors might try to find a way in.

Vulnerability scanning is vital to securing your production environments, so selecting the right DAST tool for the job is a serious undertaking. But DAST can also be used for security scanning in the development process – so do you need separate DAST tools for vulnerability management in production and for building secure software? Knowing what to look for in a DAST solution can make the difference between having one or many subpar tools that only tick boxes and getting an industrial-grade product that helps you take control of all your AppSec.

What are dynamic application security testing tools?

DAST tools (also called vulnerability scanners) perform security tests on a running application. They automate many of the steps of manual penetration testing and – if they’re accurate and reliable enough – can provide a security baseline in between manual tests. With a good DAST tool, security teams don’t have to wait for external test results or spend days manually investigating and confirming scan results. As part of a broader cybersecurity program, DAST tools complement other testing methods to maximize visibility into your security posture. 

Apart from identifying security vulnerabilities, a good DAST scanner will also report the location of each issue and technical details of how the application responded to its test payload. This additional information is crucial to speed up prioritization and remediation. Some DAST tools also integrate into the software development lifecycle (SDLC), making them dual-purpose: for scanning in production and for early testing during development. 

DAST strengths to ask about that make a difference in DevSecOps

Out of all the benefits that DAST brings, several capabilities are crucial for vendor and product selection, especially when looking for DevSecOps tools that will work in your CI/CD pipeline. If your vendor of choice falls short in these areas or fails to deliver clear information when pressed, it’s a warning sign that their DAST tool might not help you accomplish your application security goals. Here’s a quick overview of DAST essentials – and if you want to dive deeper, our free web application security buyer’s guide is a good place to go next.

SDLC integration

Any security tool that’s supposed to work in a DevOps setting to build DevSecOps has to integrate with automated workflows. This is especially important for DAST as the one type of security testing you can use at several points in the development and operations process.

From issue trackers to continuous integration and deployment tools and web application firewalls (WAFs), a DAST solution for DevSecOps needs to integrate and interact with multiple systems for both manual and automated use. To cut down on manual integration work and deployment times, look for solutions with built-in workflow integrations with software you already use in your SDLC. And because customized or completely bespoke systems are a fact of life, also ask your DAST vendor about an internal API, no matter what integrations come in the box.

Automated efficiency

DAST tools take a real-world threat approach to security by safely performing simulated attacks on running applications. Doing this allows a scanner to test the app from the point of view of a malicious hacker, looking for entry points and vulnerabilities that might have gone unnoticed during code reviews – or weren’t even there until deployment.

An efficient tool can scan and rescan any subset of assets as often as you need, whether launching automatically in a workflow, running on schedule, or doing a one-off test. Because DAST scanners can automate testing and deliver feedback quickly, they can cut down on the time teams need to spend manually gathering and checking security results.

Accuracy and depth 

Modern web applications are often very complex and dynamic. A winning DAST tool needs to do more than scratch the surface by looking for patterns in server responses – it has to include a full web browser engine to interact with the application and access and test every last parameter. Always look for a DAST tool that comes with comprehensive scanning and crawling capabilities, including support for authenticated scanning, so you don’t risk missing any security gaps.

Some DAST scanners not only identify vulnerabilities but also provide additional features for a more accurate view of your risk landscape. Depending on the product, these can include web asset discovery, web technology stack detection, dynamic software composition analysis (SCA) to identify vulnerable open-source dependencies, and even interactive application security testing (IAST) functionality.

Technology-agnostic testing

One of the main strengths of DAST scanners is that you can (in principle) use them to test any website or application, regardless of the technology stack and programming languages used under the hood. This is because DAST tools don’t need source code access to scan an application – if it has a web interface, a good scanner should be able to test it.

Some older vulnerability scanners were designed for mostly static pages and had very limited support for JavaScript. Any serious modern tool needs to run, crawl, and fully test scripting-heavy apps, including single-page applications (SPAs), so make sure you specifically ask about this.

Taking control of false positives

Probing an app with automated mock attacks runs the risk of getting noisy, so the most effective DAST tools are explicitly designed to weed out false positives – those pesky false alarms that DevSecOps teams and developers have to evaluate manually.

Even though DAST scanners tend to have lower false positive rates than tools for static application security testing (SAST), they still have to find ways to maximize the testing scope without overreporting. When evaluating DAST solutions, keep an eye out for automated verification technologies like proof-based scanning that can immediately show which results are directly exploitable, giving your team more confidence in the scan results. 

Streamlined security compliance

Meeting regulatory requirements related to security risks can become difficult for organizations that don’t have accurate, reliable tools. That’s especially true in industries like healthcare and the public sector, where compliance with specific regulations needs to be controlled on a daily basis, not only when the audit rolls around.

With a high-quality DAST tool that includes compliance reporting for accepted standards like HIPAA or PCI DSS, preparing for and maintaining compliance with application security requirements becomes far easier and more cost-efficient. 

API security testing

Modern web applications rely on APIs for everything from accessing and exchanging data to internal communication between app components. With an estimated 400% rise in API attacks from the end of 2022 to the beginning of 2023, it is vital to make API security an integral part of the broader cybersecurity program.

Many API security efforts focus on gateways and other ways to restrict access, with API vulnerability testing being limited to manual tests. A quality DAST scanner should be able to cover APIs as well as GUI apps, supporting the most common API types (especially REST), API specification file formats, and authentication methods to help you scan your APIs for vulnerabilities in the same way as your websites and applications.

A recipe for success: What are the best DAST tools for DevSecOps?

Finding and selecting the best DAST tool for your needs is a process that requires thoughtful consideration not only of your security and IT needs but also of your business goals and development and security workflows. Security is a process, not a one-off purchase. Any vendor worth their salt should go far beyond trying to sell you a product and aim to become a trusted partner and advisor in your application security journey.

At Invicti, expert setup and support resources help ensure you’re getting the most out of your investment in DAST. That way, you can embed automated security best practices into development and let your teams focus on what matters most: building innovative applications for your employees and customers.

Want to see Invicti’s best-in-DAST solution in action? Book a demo

Frequently asked questions

Can you use DAST in DevSecOps?

You can and you should use DAST in DevSecOps, since automated dynamic testing is a perfect match for DevOps workflows. It is the only approach to automated application security testing that doesn’t require source code access and can be used both during development and in production. However, not all DAST tools can easily integrate into DevOps processes, and not all can provide the accuracy required to prevent clogging your development teams’ issue trackers with false positives or non-actionable results.
 
Learn more about using DAST in the SDLC

Is DAST or SAST better for DevSecOps?

DevSecOps should incorporate security testing into the entire development and operations cycle. While they are useful to flag security issues as early as possible, static analysis (SAST) tools work on the source code, so they can only be used during development and only when the source code is available. DAST tools can be used at multiple points of the DevOps pipeline and test any runnable web application, from early builds to final production deployments – regardless of whether you have the source code.
 
Learn more about DAST vs. SAST vs. IAST

What’s the difference between doing DevOps plus security and doing DevSecOps?

An agile DevOps process relies on maximum automation for rapid development and frequent deployment in short release cycles. If security testing and remediation are not automated to the same level, security will hold development back, leading to delays and internal tensions. The DevSecOps approach aims to make security testing a routine and efficient part of the DevOps pipeline by integrating tools such as accurate and automated DAST.
 
Learn more about the shortcomings of traditional security testing in agile development

Zbigniew Banach

About the Author

Zbigniew Banach - Technical Content Lead & Managing Editor

Cybersecurity writer and blog managing editor at Invicti Security. Drawing on years of experience with security, software development, content creation, journalism, and technical translation, he does his best to bring web application security and cybersecurity in general to a wider audience.