Implementing DAST in DevSecOps

In today’s fast-paced software development landscape, ensuring the security of applications is a critical priority. With the rise of DevSecOps—the integration of security practices within the DevOps pipeline—organizations can automate security checks and identify vulnerabilities early in the development lifecycle. One such essential security practice is Dynamic Application Security Testing (DAST).

What is DAST?

Dynamic Application Security Testing (DAST) is a security testing method that focuses on identifying vulnerabilities in web applications while they are running. Unlike Static Application Security Testing (SAST), which analyzes the source code, DAST interacts with a live web application to find issues such as SQL injections, cross-site scripting (XSS), and other exploitable vulnerabilities.

The goal of implementing DAST in a DevSecOps pipeline is to automate this testing process, allowing teams to catch security flaws before code moves to production.

Implementation of DAST in DevSecOps

1. Choose the Right DAST Tool

The first step is selecting the appropriate DAST tool for your DevSecOps pipeline. The tool should integrate well with your existing CI/CD process, be compatible with your tech stack, and support automated scans.

Some popular DAST tools include:

• OWASP ZAP (Zed Attack Proxy): An open-source tool widely used for DAST testing.

• Burp Suite: A comprehensive security testing tool for web applications.

• Acunetix: A powerful DAST tool designed for automated scanning.

• Netsparker: Offers automated vulnerability scanning with deep integration capabilities.

Criteria to consider when choosing a tool:

• Integration with CI/CD tools (e.g., Jenkins, GitLab, Azure DevOps)

• Coverage of common vulnerabilities (e.g., OWASP Top 10)

• Support for multiple application environments (e.g., cloud, on-premise)

• Automation and reporting capabilities

2. Set Up the DAST Environment

Before running DAST scans, set up a testing environment. DAST tests your application in a running state, so you'll need to deploy it in an environment that closely mirrors production but is safe to run penetration tests on.

• Staging Environment: It’s recommended to use a staging environment that simulates the production environment. This allows for safe and thorough testing without affecting live users.

• Test Data: Ensure that any sensitive data in the environment is obfuscated or replaced with test data.

3. Integrate DAST into Your CI/CD Pipeline

The next step is to integrate the DAST tool into your CI/CD pipeline. This allows the tool to automatically run security tests as part of the build, test, and deployment processes. The key points of integration are:

• Post-Build Scan: After the application is built and deployed to the test environment, trigger a DAST scan.

• Automated Scanning: Configure your CI/CD tool (e.g., Jenkins, GitLab CI) to trigger DAST scans automatically upon successful builds or before deployment to production.

• Reporting: Ensure that the DAST tool generates reports and logs that are accessible to the development and security teams. Integrate with your bug-tracking system (e.g., JIRA) to automatically create tickets for discovered vulnerabilities.

Example using Jenkins and OWASP ZAP:

• Install OWASP ZAP as a Docker container in your CI environment.

• Configure a Jenkins pipeline to trigger the OWASP ZAP scan after the application is deployed to the test environment.

• Set up OWASP ZAP to scan the application’s URL and generate a report on vulnerabilities.

• Parse the report in Jenkins and fail the build if critical vulnerabilities are found.

4. Customize DAST for Your Application

DAST tools typically provide default scanning rules, but you may need to customize the scans based on your application’s architecture and specific security requirements.

• Authentication: Many web applications require authentication. Configure your DAST tool to log in automatically, so it can scan protected pages. Some tools allow the use of session tokens or credentials.

• URL Whitelisting: Ensure that the DAST tool targets the relevant parts of your application and avoids unnecessary scans (e.g., third-party APIs or irrelevant endpoints).

• Thresholds: Set up thresholds to automatically flag certain vulnerabilities, like SQL injections, as high-severity issues that will break the build.

5. Run DAST Scans Regularly

Once DAST is integrated into the pipeline, schedule regular scans. DAST should run during:

• Every Build: Automate the DAST scan to run with each build of the application.

• Scheduled Runs: Even after deployment, regularly scheduled scans ensure continuous security coverage.

• Ad-hoc Scans: In addition to automated scans, you can manually trigger scans when needed (e.g., after major code changes or new features).

6. Analyze and Address Vulnerabilities

Once the DAST tool generates a report, the next step is to analyze and address the vulnerabilities found.

• Critical and High-Risk Issues: These should be prioritized and fixed immediately. Integrate your DAST tool with a bug-tracking system to automatically create tickets for high-severity issues.

• Medium and Low-Risk Issues: These can be addressed during regular development cycles or in security sprints.

• False Positives: Review results for false positives, which can sometimes be flagged by DAST tools. Whitelist any known false positives to avoid cluttering future scans.

7. Automated Feedback Loop

After addressing vulnerabilities, ensure an automated feedback loop where:

• Developers are immediately notified when a vulnerability is found.

• Scans re-run after fixes are implemented to confirm the resolution of issues.

• Security becomes part of the Continuous Integration (CI) process, giving developers immediate feedback on the security state of their application.

8. Continuous Improvement

DAST is not a one-time implementation. As your application evolves, so should your security testing practices. Continuous monitoring, regular tool updates, and improvements to testing rules will ensure that your application remains secure over time.

Best Practices for Implementing DAST in DevSecOps

1. Shift Left: The earlier you catch vulnerabilities in the development process, the cheaper and easier they are to fix. Shift DAST testing as far left as possible in the CI/CD pipeline.

2. Combine with Other Security Testing: While DAST is effective, it is only one piece of the puzzle. Combine DAST with SAST (Static Application Security Testing) and RASP (Runtime Application Self-Protection) to cover all stages of application security.

3. Tune DAST Rules Regularly: Regularly update DAST rules based on the evolving nature of your application and new vulnerabilities discovered in the security landscape.

4. Educate Your Team: Security should be a shared responsibility. Ensure your development and operations teams are aware of common vulnerabilities, how to fix them, and how to interpret DAST reports.

Conclusion

Integrating DAST into your DevSecOps pipeline is an essential step in ensuring your web applications are secure and resilient against attacks. By automating dynamic security testing, you can detect vulnerabilities in real-time and fix them before they impact production.

With a solid DAST implementation, your organization can continuously monitor, test, and improve security, aligning with the core principles of DevSecOps—speed, security, and collaboration.