In today’s digital landscape, security testing has become an indispensable part of the software development lifecycle. With cyber threats evolving constantly, it’s crucial for organizations to ensure the security of their applications. Among the various approaches to security testing, four prominent methods stand out: Static Application Security Testing (SAST), Dynamic Application Security Testing (DAST), Interactive Application Security Testing (IAST), and Runtime Application Self-Protection (RASP). Each method has its own strengths and weaknesses, making them suitable for different stages of development and types of applications. Understanding the differences between these approaches is essential for organizations aiming to build robust, secure software. In this article, we’ll explore the characteristics of SAST, DAST, IAST, and RASP, along with their differences and use cases.


DefinitionAnalyzes application source codeTests the application during runtimeCombines elements of SAST and DASTProtection mechanism integrated into the application runtime
AutomationFully automatedFully automatedRequires instrumentation, partially automatedFully automated
TimingDone during developmentDone post-development, pre-productionDone during runtimeActive during runtime, integrated with application code
CoverageEntire codebaseFunctional aspects accessible from outsideSpecific code execution pathsEntire application runtime
Performance ImpactLowModerate to HighLow to ModerateLow to Moderate
ExamplesCheckmarx, Fortify, VeracodeBurp Suite, OWASP ZAPContrast Security, Checkmarx IASTWaratek, Prevoty, Contrast Security
Detection MethodSource code analysisBlack-box testing, HTTP traffic analysisHybrid of source code analysis and runtime testingMonitors runtime behavior and blocks attacks
Vulnerability TypeKnown vulnerabilities in the codeKnown vulnerabilities in the running applicationKnown vulnerabilities and runtime issuesKnown vulnerabilities and runtime threats
Ease of UseRequires access to source codeEasy to use, no access to source code requiredRequires access to source code and runtime environmentEasy to use, no access to source code required
AccuracyHighModerateModerate to HighHigh
Remediation TimeEarly in the development cyclePost-development, pre-productionEarly in the development cycleContinuous, throughout the application runtime
False PositivesModerate to LowHighModerate to LowModerate to Low
IntegrationIntegrated into CI/CD pipelinesIntegrated into CI/CD pipelinesIntegrated into CI/CD pipelinesIntegrated into the application runtime



  1. SAST (Static Application Security Testing):
    • Tool: Checkmarx
    • Process: Analyzes the source code of an application without executing it.
    • Example: Identifying hardcoded passwords in the source code.
  2. DAST (Dynamic Application Security Testing):
    • Tool: OWASP ZAP (Zed Attack Proxy)
    • Process: Tests the application from the outside. It’s a black-box testing method.
    • Example: Identifying SQL injection vulnerabilities by sending malicious requests to the application.
  3. IAST (Interactive Application Security Testing):
    • Tool: Contrast Security
    • Process: Combines elements of SAST and DAST, running while the application is being developed and tested.
    • Example: Identifying security vulnerabilities in real-time during application runtime.
  4. RASP (Runtime Application Self-Protection):
    • Tool: Waratek
    • Process: Protection mechanism integrated into the application runtime.
    • Example: Detecting and blocking SQL injection attacks in real-time.


In an era where data breaches and cyber attacks are rampant, robust security measures are non-negotiable for any software application. By leveraging a combination of Static Application Security Testing (SAST), Dynamic Application Security Testing (DAST), Interactive Application Security Testing (IAST), and Runtime Application Self-Protection (RASP), organizations can significantly enhance their security posture. While each approach has its own strengths and weaknesses, integrating multiple methods into the development lifecycle provides comprehensive protection against a wide range of threats. By understanding the differences between these security testing techniques and implementing them effectively, organizations can minimize security risks and build applications that are resilient to cyber threats.