Understanding the Difference Between DAST vs. SAST for Application Security Testing

TL;DR

• DAST and SAST are two different approaches to application security testing.
• DAST scans applications from the outside, while SAST analyzes source code.
• DAST is language-agnostic and provides a realistic assessment, while SAST is language-dependent.
• Automated tools can’t compare to the Synack Platform and its comprehensive, human-led approach to application security testing.

With all the different types of application security testing tools and solutions on the market today, it can be hard to determine which tool does what, where they’re needed and how effective they can be. Let’s start with DAST and SAST.

DAST and SAST are two different approaches to application security. SAST, or Static Application Security Testing, scans the source code of an application to identify vulnerabilities within the code itself. DAST, or Dynamic Application Security Testing, tests the application from the outside, simulating an attacker’s perspective. While SAST is code language-dependent and may produce more false positives, DAST is code language-agnostic and provides a more realistic assessment of the application’s security. While they may sound similar, their differences are important to note. This post will explore the differences between DAST and SAST, their strengths, limitations and how the Synack Platform beats out both with a human-led approach to security testing.

Understanding the Difference Between SAST and DAST for Application Security Testing

Application security is a critical aspect of software development. While there are several different tools and solutions, two primary methods used to test for vulnerabilities are Dynamic Application Security Testing (DAST) and Static Application Security Testing (SAST). Both methods aim to identify security weaknesses, but they differ in their methodology and the stage at which they are implemented in the software development lifecycle (SDLC).

DAST: Utilizing an External Approach for Application Security Testing

DAST, also known as black-box testing, is a method that focuses on scanning applications and APIs to identify vulnerabilities that could potentially be exploited by external malicious hackers. Unlike SAST, DAST does not require access to the source code and can be performed on running applications. By simulating real-world attacks, DAST provides a comprehensive view of the application’s security posture.

Exploring the Advantages and Limitations of Dynamic Application Security Testing (DAST)

DAST is technology-independent, meaning it can effectively scan and identify vulnerabilities regardless of the programming languages or frameworks your application is built on. It is particularly useful for detecting misconfigurations, authentication and encryption issues, and testing API and web services. However, DAST is limited to scanning web applications and services, and it’s worth noting that it has a high false positive rate, potentially adding more work for security teams.

DAST is typically implemented later in the development lifecycle, once there is a working application running in a test environment. This means that vulnerabilities may only be discovered towards the end of the development process. Nonetheless, integrating DAST into the CI/CD pipeline can help ensure maximum security and minimize the risk of releasing vulnerable software.

SAST: Employing Source Code Analysis for Application Security Testing

SAST, on the other hand, is a white-box testing approach that focuses on scanning the source code of an application to identify vulnerabilities. By analyzing the source code, SAST can detect potential security weaknesses early in the software development lifecycle. This allows developers to address these issues before they become more complex and costly to fix.

Exploring the Advantages and Limitations of Static Application Security Testing (SAST)

SAST is great for software development teams who are looking for deficiencies within their application code. SAST can surface a range of potential problems and often, teams can see results in real-time. However, while there are advantages to using automated tools like SAST, there are some disadvantages that organizations and security teams should consider. 

SAST can only identify vulnerabilities within source code and is not designed to discover issues related to user input. Pattern-based scanning can also lead to an overwhelming amount of potential vulnerabilities, with a majority of them being false positives or low-hanging fruit. Like DAST, this can add unnecessary and extra work for developers and security teams.

FAQs

What is static application security testing or SAST?

Yes, static application security testing is also known as SAST. It involves analyzing source code to identify security vulnerabilities in applications before they are compiled. So, SAST is the same as static application security testing.

Understanding DAST in application security

DAST, which stands for Dynamic Application Security Testing, is a method used to assess web applications by simulating attacks from the front-end. It helps identify vulnerabilities by approaching the application from an external perspective, similar to how a malicious user would target it.

Is DAST specifically for web applications?

No, DAST is not only for web applications. It can also be used for web services and thick clients. However, it may not be as useful for other types of software since it primarily focuses on dynamic analysis for finding run-time vulnerabilities.

Differentiating DAST from vulnerability scanning

Yes, DAST is similar to vulnerability scanning as it typically involves automated scanning for vulnerabilities. However, it’s important to note that DAST specifically focuses on dynamic application security testing, while vulnerability scanning can encompass a broader range of security assessments.

Partner with Synack for Superior Application Security Testing

While both DAST and SAST have their own unique strengths and circumstances where they are proven to be beneficial, it’s important to note that automated tools are no match for human talent and will not discover the critical vulnerabilities that malicious hackers are actively trying to exploit. These scanners uncover what’s at the surface, but fail to detect the flaws or software issues that CISO and CIOs need fixed. All in all, automated solutions are simply no match for human ingenuity. That’s why organizations use the Synack Platform for superior application security testing.

The Synack Red Team, our elite, highly-vetted community of security researchers, works to discover exploitable vulnerabilities across your mobile, web and cloud applications, and our platform provides actionable and real-time data into root causes so your team can prevent them from reappearing. The SRT, in addition to automated tools, looks for common and critical vulnerabilities like those in the OWASP Top 10, the OWASP Web and Mobile Security Testing Guides (WSTG, MSTG) and more. 

The Synack Platform harmonizes security and development teams with continuous testing on a platform that prioritizes flaws that need to be fixed. Our researchers are testing 24/7/365, through weekends and holidays and our vulnerability operations teams triage and verifies flaws so your team only focuses on what needs to be addressed and avoid false positives. If you’re interested in learning more about our application security testing solution, request a demo today.