SAST vs. DAST: Understanding the Difference with Tool Examples

Introduction

In the world of cybersecurity, two powerful methods are used to identify and fix security vulnerabilities in software: SAST (Static Application Security Testing) and DAST (Dynamic Application Security Testing). While they may sound technical, understanding these concepts is simpler than you think. Let’s break them down and explore how tools like Snyk and Qualys play a role in keeping software secure.

What is SAST?

• Layman’s Terms: SAST is like proofreading a book before it’s published. It checks the code for mistakes and vulnerabilities without actually running the software.

• Explanation: SAST analyses the source code, byte code, or binary code of an application to identify security vulnerabilities. It’s a proactive approach that helps developers catch issues early in the development process.

Example Tool: Snyk

• What it Does: Snyk is a developer-friendly SAST tool that integrates directly into your development environment. It scans your code in real-time, identifies vulnerabilities, and even suggests fixes.

• Features:

  • Real-time scanning while coding.

  • Auto-fixes for vulnerabilities.

  • Integration with popular IDEs and CI/CD pipelines.

• Use Case: A developer uses Snyk to scan their codebase for vulnerabilities like SQL injection or cross-site scripting (XSS) while writing the code. Snyk provides actionable insights and fixes, ensuring secure code from the start.

Other Examples of SAST Tools:

1. Checkmarx: A popular tool that scans code for vulnerabilities and provides detailed reports to help developers fix issues.

2. SonarQube: An open-source platform that continuously inspects code quality and security.

3. Veracode: Offers comprehensive security analysis and integrates with development workflows.

What is DAST?

• Layman’s Terms: DAST is like test-driving a car to see if anything goes wrong. It checks the software while it’s running.

• Explanation: DAST tests an application in its running state to find vulnerabilities that could be exploited by attackers. It simulates real-world attacks to identify security weaknesses.

Example Tool: Qualys

• What it Does: Qualys Web Application Scanning (WAS) is a DAST tool that scans running web applications for vulnerabilities. It identifies issues like misconfigurations, broken authentication, and insecure data handling.

• Features:

  • Scans live applications for vulnerabilities.

  • Provides detailed reports with remediation steps.

  • Scalable for large environments.

• Use Case: A security team uses Qualys WAS to scan a live web application for vulnerabilities like broken access control or sensitive data exposure. The tool provides a report with actionable recommendations to fix the issues.

Other Examples of DAST Tools:

• Acunetix: A web vulnerability scanner that detects and reports on a wide range of security issues.

• OWASP ZAP: An open-source tool that helps find security vulnerabilities in web applications.

• Netsparker: An automated web application security scanner that identifies vulnerabilities and provides actionable insights.

Key Differences Between SAST and DAST

Why Use Both?

Using both SAST and DAST provides comprehensive security coverage:

• SAST: Helps developers catch vulnerabilities early, saving time and costs.

• DAST: Identifies vulnerabilities that only appear when the application is running, ensuring real-world security.

Conclusion

SAST and DAST are essential tools in the cybersecurity toolkit. While SAST focuses on finding vulnerabilities in the code during development, DAST tests the application in its live environment to uncover real-world risks.

By combining SAST and DAST, you can ensure your applications are secure from development to deployment. Understanding these tools and their benefits is a step toward creating a safer digital world.