How to implement DAST: A complete guide to dynamic application security testing

How to implement DAST effectively—quickstart guide

Dynamic application security testing (DAST) is a powerful method for finding vulnerabilities in web applications. By simulating actual potential attacks, DAST works to provide an outside-in view of risk and threats for running applications so that teams know how they might be exploited in real-world attacks. If you want to maximize the effectiveness of DAST and improve your security posture, you need to implement it strategically.

1. Selecting a DAST tool

Depending on the vendor and their strengths, DAST tools vary in features, pricing, and ease of use. Choosing the right tool depends on your application architecture, budget, and security needs. Carefully consider the breadth of coverage (i.e. can your tool of choice find dangerous vulnerabilities like cross-site scripting (XSS), SQL injection (SQLi), and misconfigurations?) and also whether or not your tool or platform of choice has automated workflows.

Popular DAST tools

• Open-source tools
  • OWASP ZAP: Great for beginners; integrates well with DevSecOps
  • Wapiti: Simple, fast, and lightweight CLI-based scanner
• Enterprise solutions
  • Invicti (formerly Netsparker): Offers self-learning capabilities and automatic verification of security vulnerabilities
  • Burp Suite Professional: Popular among security testers; allows manual exploitation
  • Acunetix: Comprehensive scanning with compliance reporting for improved security posture

Pro tips

• Go beyond default configurations: Many DAST tools have pre-set scanning rules, but tweaking them for your specific tech stack ensures deeper analysis.
• Choose a tool with authentication support: Many vulnerabilities lie behind login pages, so pick a tool that can handle multi-step authentication.
• Consider false positive handling in scan results: Application security (AppSec) platform solutions like Invicti can automatically confirm vulnerabilities in the software development lifecycle (SDLC), reducing manual verification efforts.

2. Integrating DAST into the development pipeline

Web application security should be an ongoing process, not just an afterthought. Integrating DAST and other application security testing tools into your DevSecOps pipeline helps catch vulnerabilities early.

Integration methods

• CI/CD integration: Run scans within Jenkins, GitHub Actions, GitLab CI/CD, or Azure DevOps
• Staging/pre-production testing: Before deploying updates, conduct DAST scans to ensure security
• Scheduled scans: Automate weekly or bi-weekly scans for continuous monitoring of security issues

Pro tips

• Start small, scale later: Instead of scanning the entire web app daily, start with critical pages and gradually expand.
• Use parallel testing: Run DAST scans in non-production environments to avoid impacting performance.
• Combine your DAST solution with SAST, IAST, and SCA: DAST finds runtime vulnerabilities, but SAST (static application security testing), IAST (interactive application security testing), and SCA (software composition analysis) can catch deeper issues in source code throughout application development and beyond.

3. Configuring scans for maximum effectiveness

Poorly configured scans result in missed vulnerabilities or excessive noise in cybersecurity. Proper configuration and reliable testing methods help achieve accurate results that both development and security teams are proud of.

Key configuration steps

• Define target scope: Set clear boundaries to avoid scanning third-party components unintentionally.
• Authentication setup: Use session cookies, API keys, or OAuth to scan protected areas.
• Attack surface discovery: Enable crawling to find hidden URLs and entry points.
• Rate limiting and throttling: Prevent overwhelming your servers with too many requests at once.

Pro tips

• Use authenticated scans: Most critical vulnerabilities are behind login screens, so configure authentication properly.
• Enable input fuzzing: Some tools allow custom payloads for better attack simulation.
• Set up exclusion rules: Avoid scanning endpoints like logout pages or third-party integrations to reduce noise.

4. Executing tests: running the DAST scan

Once configured, it’s time to run the DAST scan. This process can take anywhere from a few minutes to several hours, depending on application complexity.

Types of DAST scans

• Passive scanning: Observes traffic without actively sending malicious payloads
• Active scanning: Actively injects attack payloads to test for vulnerabilities
• Authenticated scanning: Accesses user-restricted areas

Pro tips

• Test in a staging environment first: Running DAST on production can impact performance.
• Monitor application behavior: Certain tests may cause application crashes or unintended behaviors.
• Run incremental scans: Instead of running full scans every time you do a security check, target areas that have changed recently or are cause for concern.

5. Analyzing results and prioritizing fixes

DAST scanner reports can contain hundreds of potential vulnerabilities, but not all are critical. Focus on fixing the most dangerous ones first.

Prioritization criteria

• Severity level: Critical, High, Medium, Low
• Exploitability: How easily can an attacker use this vulnerability?
• Business impact: Does this affect sensitive user data?

Pro tips

• Don’t blindly trust the report: Verify critical issues manually before fixing them.
• Use risk-based prioritization: First focus on remediating vulnerabilities that impact authentication, data security, or remote code execution.
• Filter out false positives: Some vulnerabilities may be flagged incorrectly; use manual verification where needed.

6. Remediation and continuous improvement

Fixing vulnerabilities is just the beginning. To maintain security, DAST should be part of an ongoing security program.

Remediation best practices

• Work with development teams: Provide clear descriptions of vulnerabilities and how to fix them.
• Use secure coding guidelines: Implement best practices to prevent recurring issues.
• Retest after fixes: Always re-run scans after making security fixes.

Pro tips

• Educate your dev team: Teach developers about common vulnerabilities (e.g., OWASP Top 10) to prevent recurring issues.
• Automate security testing: Use scheduled scans to continuously monitor security instead of solely relying on manual testing.
• Track progress over time: Maintain a history of vulnerabilities and security flaws to measure security improvements.

Ready to get started with DAST?

It’s indisputable that DAST is an essential part of a strong security strategy today. However, it works most effectively when combined with other security tools and practices. By properly configuring scans, integrating them into the CI/CD pipeline, and prioritizing fixes, you can significantly reduce security risks.