What is DAST?

With heightened cybercriminal activities around us, all online enterprises need to know how to defend against application layer attacks.

Since proactive defense is always better than reactively scrambling to rebuild defenses after a successful intrusion, most successful enterprises rely on DAST tools to bolster their application security and identify possible threats before they are realized.

Let’s break down what DAST tools are and how they might help your enterprise in the future.

What is Dynamic Application Security Testing (DAST)?

DAST, or Dynamic Application Security Testing, is a category of web scanning tools that can help find various security vulnerabilities in certain web applications. It is said to replicate an attack carried out by a hacker on your application to give the best possible results. 

Rather than looking for issues from the inside, DAST tools conduct a scan of vulnerabilities from the exterior of a web application without accessing source code architecture. For this reason, DAST is commonly classified as a “black box” security solution.

How Does DAST Work?

DAST scanners work utilizing two key parts: a “crawler” element that can explore a web application and discover all the URLs possible and a “detection” element that can execute various requests against URLs individually. In this way, DAST scanners both find and “attack” URLs in a web application to test them for various vulnerabilities.

To use a DAST tool, a network administrator or operator directs the scanner to target a home URL. The crawler element starts to navigate through different URL links through the primary URL. This does limit DAST tools to URLs that are accessible from the home page.

However, most DAST scanners also have options to let you enter additional URLs manually.

After building a list of suitable URLs, a DAST scanner will run through a list of various request formats, usually involving payload attacks to test a network for certain types of security issues.

The list of request formats can be personalized based on the technologies of the system in question or based on likely cyberattacks.

Depending on the sophistication of the DAST tool and the number of URLs to test, this process can take up to several days.

DAST Can Give Crucial Security Insight

A DAST scan can provide lots of actionable information for a network administrator or IT security team. Specifically, feedback can include:

• The types of security vulnerabilities encountered/detected
• Which URLs were affected by the security vulnerabilities
• Any additional parameters that might have affected the request

DAST tools are, therefore, best at testing the HTML and HTTP interfaces of web applications to simulate the kinds of attacks a cybercriminal would use to get into a service or application.

It’s a proactive type of security testing that can help catch issues where trawling through hundreds of lines of code would be impractical or less than helpful.

Why is DAST Important?

DAST holds significance in application development as it provides a crucial layer of security beyond developers’ expertise. Conducting DAST during the SDLC enables the early detection of vulnerabilities before deployment, averting potential data breaches and protecting brand reputation. 

By mimicking hackers’ techniques, DAST identifies security gaps from an external perspective, aligning with industry standards such as PCI DSS and HIPAA. Given the inevitability of human error in the SDLC, detecting vulnerabilities early via DAST minimizes costs associated with remediation.

Benefits of DAST

DAST tools aren’t perfect and everything, but they do provide several benefits that might make them a good choice for your web application over SAST or other tools.

• Totally Application Independent: Because DAST tools don’t delve into an app’s source code, they can be used regardless of the platform or language you’re working with. As a result, a single DAST tool can run on all your applications, and can even be utilized for applications that are different from one another but may nonetheless interface frequently.

• No Configuration Issues: When your application is fully operational, DAST does a great job of finding security vulnerabilities. Since it looks at your application from an outside perspective, a DAST scanner is perfectly positioned to discover configuration mistakes that might be missed by other types of security scanning tools.

• Not Many False Positives: The OWASP Benchmark Project, a Java-based test suite that was designed to evaluate how well different software vulnerability detection tools performed found that DAST tools had a lower-than-average number of false positives.

• Good Penetration Testing Utility: By manually doing penetration testing with a DAST scanner, you can automate various penetration tasks to directly see how your system responds to such intrusions and whether or not it catches different attack payloads.

Disadvantages of DAST

Although it’s wise to consider DAST security tools for your applications, there are some disadvantages you should be aware of so you aren’t caught off guard.

• Vulnerability Reporting is General, Not Specific: Since DAST doesn’t take a look at your application’s source code architecture, it can’t tell you exactly why the security vulnerability exists. Any DAST scanner report will include the type of vulnerability, which URLs were affected, and certain parameters about the request.

• Complex Risks May Go Unnoticed: The same OWASP Benchmark test mentioned above found that, while DAST had a low number of false positives, even extremely sophisticated or effective scanners can only find about 18% of existing security vulnerabilities.

• Time-Consuming: DAST scanners can, as mentioned, take up to several days to complete, especially with more complex web applications. If your team needs to push out new code pretty frequently, DAST scanners may not be effective.

• Late Application in the Software Development Process Lifecycle: Because DAST tools have to look at the outside of a web application and are most effective when used on operational applications, they’re typically deployed toward the end of an app’s development lifecycle.

Differences Between DAST and SAST

DAST tools are the only type you can use to test a web application for vulnerabilities. Another popular alternative is Static Application Security Testing, or SAST, technology. 

Refer to this table for a clearer understanding of both these application security testing methods. 

As “white box” testing tools, SAST scanners can look through the source code architecture of applications so long as they are at rest rather than currently operating.

In a way, SAST tools are the opposite of DAST scanners – they look at an application from the inside out instead of from the outside in. They also have many of the opposite benefits and drawbacks.

What are DAST Scanners?

Furthermore, DAST scanners put you in the perspective of an attacker, which can be valuable for skilled security specialists who know that most attackers won’t have access to an application’s source code anyway.

The bottom line? It’s almost always best to use both DAST and SAST scanners and tools together to cover all your bases. SAST tools should be implemented early, even if you just have one scanner tailored for your application’s programming language or architecture.

After your software has reached a later stage of the development cycle, DAST scanners should be brought into play to check for any vulnerabilities you might have missed.

How to Implement DAST?

Implementing DAST into your CI/CD pipeline requires careful planning and execution to ensure its effectiveness in identifying security vulnerabilities. Here’s a structured approach based on the provided information:

Understand User Interactions

Start by actively engaging with end-users to comprehend their application interactions. Document these actions meticulously to glean insights into their user experience. Specifically, focus on identifying areas where user interactions could reveal security vulnerabilities.

Automate User Interactions

Use automation tools to script user interactions observed during engagement, ensuring efficiency. This helps create smooth processes and maintains consistency in executing actions across varied environments. Automation aids in replicating user behavior accurately for comprehensive testing.

Integration with CI/CD Pipeline

Integrate automated user interaction scripts into your CI/CD pipeline for seamless execution. These scripts should run side by side with the DAST scanning process, mimicking real-world usage scenarios effectively. After the DAST scan concludes, thoroughly analyze the results to pinpoint security vulnerabilities within your application.

Generate and Review Reports

Create detailed reports summarizing the DAST scan results. Share these reports promptly with relevant stakeholders, including developers and security experts. Prioritize the vulnerabilities based on severity and potential impact to enhance application security effectively.

Remediate Vulnerabilities

Quickly tackle the vulnerabilities pinpointed during the DAST scan. Work closely with development teams to deploy suitable fixes. Continuously track the progress of vulnerability remediation and validate the efficacy of implemented solutions.

Incorporate Regression Testing

Add regression tests to your suite to prevent old vulnerabilities from coming back. Keep updating the suite with new usage scenarios and security checks to boost your app’s security. This proactive approach ensures continued protection against threats.

How can CloudDefense.AI Help?

CloudDefense.AI provides advanced DAST services, keeping your applications secure without needing access to their source code. Our solution conducts black-box testing, spotting vulnerabilities while your apps run, ensuring maximum security with ease. With CloudDefense.AI, you can find and fix weaknesses before they become problems, protecting your digital assets effectively.

Our platform gives your team the power to integrate security into your SDLC with automated tasks targeting critical vulnerabilities. By embedding security testing automation at every stage of the SDLC, CloudDefense.AI streamlines your development process while keeping pace with new security challenges. Our DAST scanners actively identify both compile-time and runtime issues, offering real-time protection against emerging threats across diverse environments and programming languages.

On top of all of that, CloudDefense.AI offers in-depth vulnerability insights, sorting critical issues by severity for effective risk management. Integrated seamlessly into your CI system, it catches vulnerabilities early in development, ensuring ongoing protection. Lastly, receive instant alerts on new vulnerabilities affecting your project’s dependencies, keeping your applications secure in a dynamic threat environment.

Conclusion

Ultimately, DAST tools are just one part of an excellent security toolkit and a cornerstone scanner type that all application security teams should know how to use. For the best results, combine DAST scanners with SAST scanners and use both types of tools correctly. If done right, your application will be much safer from an enterprising cybercriminal.

Anshu Bansal

Anshu Bansal, a Silicon Valley entrepreneur and venture capitalist, currently co-founds CloudDefense.AI, a cybersecurity solution with a mission to secure your business by rapidly identifying and removing critical risks in Applications and Infrastructure as Code. With a background in Amazon, Microsoft, and VMWare, they contributed to various software and security roles.