Top 10 DAST Best Practices in 2025

With 42% of companies suffering from external attacks attributed to vulnerabilities in software security, Dynamic Application Security Testing (DAST) is a valuable technique for businesses to identify vulnerabilities before attackers do.

By emulating real-world cyberattacks and identifying vulnerabilities in real-time, DAST tools provide a layer of defense against such vulnerabilities. We delve into DAST’s best practices and key limitations and how to overcome them.

10 DAST Best Practices 

We recommend checking out our in-depth article for a comprehensive understanding of DAST, including its definition, use cases, and a detailed breakdown of its pros and cons in our DAST: 7 Use Cases, Examples, Pros & Cons, article.

1. Define Clear Objectives

Defining clear objectives for DAST involves identifying the specific goals you want to achieve with your security testing. This includes understanding the scope of the testing, such as which applications, modules, or features need to be tested. Objectives should outline the vulnerabilities you aim to detect, like SQL injection, cross-site scripting, or other common security issues. Establishing clear objectives helps focus the testing efforts and ensures that resources are allocated efficiently and effectively.

2. Select the Right Tools

Selecting the right DAST tool is critical for effective security testing. The choice should be based on your application’s specific needs and environment. The tools in the market focus on different aspects of testing, such as:

• Web application security testing
• Penetration testing
• network and vulnerability scanning
• mobile application testing

If you’re in the market for DAST solutions, you can refer to our article to learn about the tools’ focus and features and compare them here. See the DAST tools’ benchmark results here.

Factors to consider include the technologies used in your application (e.g., frameworks, languages), the vulnerabilities the tool can detect, ease of integration with your existing development pipeline, and user-friendliness. Additionally, the tool should provide comprehensive reporting and support for automated scans to facilitate continuous testing.

3. Baseline Testing

Baseline testing involves performing an initial DAST scan to establish a reference point for the application’s security posture. This initial scan helps identify existing vulnerabilities and understand the current security level. Documenting the baseline test results provides a benchmark against which future scans can be compared, allowing you to track improvements and the effectiveness of remediation efforts over time. 

4. Test in a Staging Environment

Running DAST scans in a staging environment is essential to avoid potential disruptions to the production environment. The staging environment should closely mimic the production setup, including the same configurations, data, and user roles. Testing in a staging environment ensures vulnerabilities are identified and addressed without impacting live users or business operations. It also allows for more aggressive testing without the risk of causing downtime or other issues.

5. Perform Regular Scans

Security is a continuous process, and regular DAST scans are necessary to identify new vulnerabilities as they arise. Regular scanning helps maintain a proactive security posture, ensuring that vulnerabilities are detected and remediated promptly. Integrating DAST into the Continuous Integration/Continuous Deployment (CI/CD) pipeline and software development lifecycle automates the scanning process, ensuring that every new code change is tested for security issues before being deployed to production.

6. Credentialed Scanning

Credentialed scanning involves using valid user credentials to test parts of the application that require authentication. This approach helps identify vulnerabilities that only appear when a user is logged in, such as user permissions, session management, and access control. Credentialed scanning is critical for comprehensive security testing as it ensures that all areas of the application, including those behind login screens, are thoroughly tested.

7. Fine-tune Scans

Fine-tuning DAST scans involves customizing the scan configurations to focus on critical parts of the application and reduce the occurrence of false positives and negatives. This includes setting the scope of the scan to target specific areas, excluding irrelevant parts, and adjusting the sensitivity of the scans. Fine-tuning helps obtain more accurate results, making prioritizing and addressing the most significant vulnerabilities easier.

8. Remediation and Retesting

Once vulnerabilities are identified, prompt remediation is essential to minimize security risks. Remediation involves fixing the identified issues and deploying the fixes to the affected environments. After remediation, retesting is necessary to confirm that the vulnerabilities have been successfully addressed and that no new issues have been introduced. This detection, remediation, and retesting cycle helps maintain a robust security posture.

9. Stay Updated

Updating DAST tools and methodologies is crucial for detecting vulnerabilities and threats. This includes regularly updating the DAST tool with the latest security rules, patches, and configurations. Staying informed about new vulnerabilities, emerging threats, and best practices in application security helps maintain the effectiveness of your DAST efforts and adapt to the evolving threat landscape.

10. Compliance and Reporting

Aligning DAST practices with relevant compliance standards ensures your security testing meets legal and regulatory requirements.

Many modern DAST tools generate comprehensive reports from DAST scans, which help document the security posture of your applications, which is essential for audits and compliance purposes. These reports provide detailed insights into identified vulnerabilities, remediation actions, and the overall effectiveness of your security measures.

8 Key Limitations of DAST 

DAST is valuable for identifying vulnerabilities in running applications by simulating real-world attacks, but it misses deeper code issues and design flaws.

Combining DAST tools with SAST tools, which analyze source code, and IAST tools, which merge dynamic and static testing, ensures comprehensive coverage and stronger security. These are the key limitations of DAST practice; however, you may overcome those with the right best practices as outlined below.

1. Limited Coverage:

• No Access to Source Code: DAST tools test applications externally by simulating attacks but do not have access to the underlying source code. As a result, they may miss vulnerabilities that can only be identified through static code analysis (e.g., certain logic flaws).
• Partial Testing: They primarily detect runtime vulnerabilities such as cross-site scripting (XSS) or SQL injection but may miss issues like insecure configurations or business logic vulnerabilities.
• Remediation: Combine DAST with SAST and IAST. This ensures coverage of vulnerabilities DAST misses, such as logic flaws or insecure configurations, by analyzing the source code, application structure, and runtime behavior.

2. False Positives and Negatives:

• False Positives: DAST tools may flag certain security issues that aren’t actual vulnerabilities, causing unnecessary alarm and manual effort to triage and dismiss these issues.
• False Negatives: They might fail to detect some vulnerabilities due to their reliance on predefined attack patterns or failure to fully explore all application paths.
• Remediation: Implement fine-tuning scans (Best Practice #7) by customizing scan configurations and sensitivity levels. This helps reduce false positives and negatives by focusing on specific application areas and excluding irrelevant parts.

See our benchmark regarding DAST true and false negative rates.

3. Difficulty with Complex Applications:

• Single-Page Applications (SPA): Modern web applications using frameworks like React or Angular can be challenging for DAST tools to analyze because the dynamic nature of content might prevent the tool from fully simulating user interactions.
• Authenticated Areas: DAST tools may struggle to adequately test authenticated portions of an application without complex configuration to simulate login sessions and user flows.
• Remediation: Conduct credentialed scanning (Best Practice #6) to simulate authenticated sessions and ensure thorough testing of authenticated and complex areas. This helps DAST better handle SPAs and other complex environments.

4. Performance Overhead:

• Resource Intensive: DAST tools can place a heavy load on the server due to repeated requests and simulated attacks, which can affect performance or stability of the application being tested.
• Testing Time: DAST scans can be slow, especially for large applications, which might delay the development process.
• Remediation: Perform DAST in a staging environment (Best Practice #4) that mimics production. This allows you to run intensive tests without affecting production performance or stability while preventing testing delays.

5. Limited Context Awareness:

• No Business Logic Testing: DAST tools do not understand the application’s business logic and might miss flaws related to the misuse of legitimate features or functionality that is secure from a purely technical perspective.
• Limited Customization: While some tools allow customization, their out-of-the-box testing often lacks the flexibility to address specific needs unique to an application’s architecture.
• Remediation: Define clear objectives (Best Practice #1) before testing, focusing on understanding the application’s business logic and specific vulnerabilities that might not be purely technical. Pair DAST with manual reviews or tools designed to test business logic flaws.

6. Inability to Detect All Vulnerabilities:

• Server-Side Issues: DAST tools generally can’t detect vulnerabilities related to server-side business logic, weak encryption, or issues like security misconfigurations in APIs that aren’t exposed during runtime interactions.
• Non-Web Vulnerabilities: These tools focus primarily on web applications and cannot identify vulnerabilities in an application’s mobile apps, desktop apps, or non-web components. Moreover, DAST is not well-suited to detecting architectural or design flaws, as it focuses on the application’s external behavior rather than how it was built or structured.
• Remediation: Ensure regular scans (Best Practice #5) and stay updated (Best Practice #9) to address evolving threats. For non-web vulnerabilities, consider additional specialized tools that complement DAST’s web-focused nature.

7. Complexity in Interpretation:

• Skill Required for Interpretation: The output of DAST tools often requires significant interpretation by security professionals. Not all findings may be relevant, and understanding the real impact of identified vulnerabilities can require additional manual analysis.
• Remediation: Use tools with strong compliance and reporting (Best Practice #10) features to generate actionable insights and detailed reports. Ensuring that security professionals skilled in interpretation review these findings can help reduce misinterpretation.

8. Dependency on Test Environment:

• Dependency on a live environment: DAST is conducted in a live environment, so its effectiveness depends on the accuracy of the test environment. If the test environment does not accurately reflect the production environment, the results may not be fully reliable.
• Inability to Find Design Flaws: DAST is not well-suited to detecting architectural or design flaws, as it focuses on the application’s external behavior rather than how it was built or structured.
• Remediation: Run tests in an environment that accurately reflects production using baseline testing (Best Practice #3). Documenting the baseline security posture allows you to detect discrepancies and improve the accuracy of results.