Understanding the Fundamental Differences

SCA, SAST, and DAST address different aspects of application security, each with distinct methodologies and coverage areas. SCA specifically targets the 80-90% of modern applications composed of third-party components, identifying known vulnerabilities, license risks, and supply chain threats. It operates by analyzing dependency manifests, binaries, and containers to create comprehensive component inventories, then matching these against vulnerability databases and license repositories.

SAST examines custom source code, bytecode, or binaries without executing the application. It identifies security flaws in code written by your development team through pattern matching, data flow analysis, and control flow analysis. SAST excels at finding issues like SQL injection in custom code, hardcoded credentials, and business logic flaws. However, it cannot analyze third-party components effectively because it lacks access to their source code and the vulnerability intelligence required for component analysis.

DAST takes a black-box approach, testing running applications by simulating attacks from an external perspective. It identifies vulnerabilities that manifest during runtime, including configuration issues, authentication flaws, and injection vulnerabilities. DAST discovers problems that static analysis might miss, such as runtime behavior emergent from component interactions. However, it provides limited visibility into the root cause of issues and cannot determine which specific component contains a vulnerability.