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3 Reasons DAST is more effective than IAST

by   in Cybersecurity

DAST (short for "Dynamic Application Security Testing") and IAST (short for "Interactive Application Security Testing") are both techniques for testing the security of web applications. While both approaches have their advantages and disadvantages, DAST is generally considered to be better than IAST for several reasons. 

3 Reasons DAST is more effective than IAST

  1. DAST is a black box testing technique, which means that it tests the security of an application without having access to its source code or internal workings. This makes it well-suited for testing the security of applications that are already deployed in production, as it can be performed without requiring access to the application's source code. In contrast, IAST requires access to the application's source code and runtime environment, which can make it more difficult to use in production environments. 
  1. DAST is generally considered to be more comprehensive than IAST, as it is able to test a wider range of security vulnerabilities. DAST tools typically use a combination of automated and manual testing techniques to identify a wide range of security issues, including vulnerabilities in the application's code, configuration, and dependencies. IAST, on the other hand, is typically more limited in scope, as it focuses on identifying and mitigating vulnerabilities in the application's code. 
  1. DAST is typically easier to use and more user-friendly than IAST. DAST tools are typically designed to be used by security professionals with little or no programming experience, whereas IAST tools require a deeper understanding of the application's code and runtime environment. As a result, DAST is often the preferred approach for organizations that want to quickly and easily test the security of their applications. 

What is DAST and why is it important? 

Dynamic Application Security Testing (DAST) is the process of analyzing a web application through the front end and APIs to find vulnerabilities through simulated attacks on a running application. This type of black box testing approach evaluates the application from the “outside in” by attacking an application as a malicious user would and does not require access to source code. Dynamic analysis can identify runtime vulnerabilities such as logic weaknesses, server misconfiguration, weak authentication, and other problems likely to be encountered after a user is logged into the application. 

DAST scanners have long been a favorite tool of enterprise security teams, Quality Assurance

(QA) teams, and penetration testers. DAST scans inject real, known attacks into a running application. As the DAST scanner performs these attacks, it looks for results that aren’t part of the expected result set and identifies security vulnerabilities. Because these tests get data out of the application and validate the results as unexpected, DAST results provide high confidence of exploitable vulnerabilities and clear surfacing of application security risk. DAST is often used alongside Static Application Security Testing (SAST) and Software Composition Analysis (SCA) tools. 

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Application security
  • Having RASP already deployed in the environment, requiring access to the application's source code and runtime environment are no issues.

    Can you provide evidence to support the claims: "DAST is generally considered to be more comprehensive than IAST" and "DAST is typically easier to use and more user-friendly than IAST", please?

    Philippus (Percy) Rotteveel
    Global Director AppSec Strategy - Fortify
    percy@microfocus.com | (650) 683-2339