Security Scanning Integration in DevSecOps Pipelines: Comparative Effectiveness of SAST, DAST, SCA, and Container Image Scanning Across Vulnerability Classes
Automated security scanning has become an integral component of DevSecOps pipelines, yet practitioner selection of scanning tool categories is frequently driven by tool familiarity rather than empirical evidence of coverage effectiveness across vulnerability classes. This paper presents a controlled empirical evaluation of four scanning modalities — Static Application Security Testing (SAST), Dynamic Application Security Testing (DAST), Software Composition Analysis (SCA), and Container Image Scanning — across a benchmark corpus of 3,600 intentionally introduced vulnerabilities spanning 18 CWE categories in Python, Java, and Node.js applications. We find that no single scanning modality achieves greater than 58% coverage across all CWE categories, and that modality coverage profiles are largely complementary: SAST excels at injection and logic vulnerabilities, DAST at authentication and session management issues, SCA at known CVE-catalogued dependency vulnerabilities, and Container Scanning at OS-layer and configuration vulnerabilities. A pipeline implementing all four modalities achieves 84.3% aggregate vulnerability coverage. We introduce the Security Scanning Coverage Matrix (SSCM) as a decision tool for pipeline architects and evaluate 12 commercial and open-source tools — including Semgrep, SonarQube, OWASP ZAP, Snyk, and Trivy — against the matrix. We also analyze false positive rates and their impact on developer adoption, finding that false positive rates above 18% trigger systematic alert fatigue and scanning suppression.
