Modern application security depends on understanding what’s in your code, both the source code you write, and the third-party components you rely on. As software development accelerates and organizations adopt DevSecOps practices, teams face rising pressure to detect security vulnerabilities earlier in the software development lifecycle and strengthen their overall supply chain security posture.
Most applications today depend heavily on open-source libraries while also maintaining large volumes of proprietary code. This creates two distinct but equally important categories of security risks: issues introduced through your own secure coding practices, and risks introduced through external dependencies. That’s why static application security testing (SAST) and software composition analysis (SCA) have become foundational to modern vulnerability management.
This guide compares SAST vs. SCA, explains how each works, and shows why using both is essential for improving application security across your entire software supply chain.
The overwhelming majority of applications (upwards of 97%) use at least one open-source component. While open-source software enables faster development, it also introduces third-party component risks that may be difficult to track manually — especially if your team is not continuously monitoring libraries for new vulnerabilities or patches.
Software composition analysis (SCA) helps teams identify and manage vulnerabilities in open-source components as part of a secure SDLC. At a glance, Kiuwan’s SCA capabilities allow development and security teams to:
Because nearly every application depends on open-source libraries, SCA is always necessary, especially before initial deployment. Teams can run SCA during development, during build processes, and after release as part of continuous monitoring to strengthen overall software supply chain security.
SAST analyzes your first-party source code for potential security vulnerabilities without executing the application. It is typically used alongside SCA and before dynamic testing (DAST) to identify insecure coding patterns early.
SAST tools evaluate your source code based on predefined rules to flag issues such as SQL injection, insecure input validation, authorization flaws, and other weaknesses that could introduce exploitable security risks.
Unlike other forms of code analysis, SAST can run at any phase of development, even before the application is functional. Because these tools pinpoint the exact file and line number where issues occur, developers can remediate vulnerabilities quickly and maintain stronger secure coding practices throughout the development lifecycle.
Your software testing team can use SAST tools at any point during development. Thanks to its static approach to detecting security vulnerabilities, it can find potential security risks in individual lines of code—meaning your team can use SAST tools at any time before deployment.
With scanning tools like Kiuwan’s SAST capabilities, developers and testers can run tests from the earliest stages of production and throughout the development process, including during QA and final checks.
While both improve application security, each targets a different part of the codebase:
Because SAST and SCA identify vulnerabilities in entirely different parts of the software supply chain, both are essential to a secure SDLC.
| Category | SAST | SCA |
| Code analyzed | Proprietary source code | Open-source and third-party components |
| Primary focus | Secure coding practices | Supply chain security & dependency risks |
| Typical findings | Logic flaws, insecure patterns, and injection vulnerabilities | Outdated libraries, license risks, known CVEs |
| When used | Throughout the SDLC, even early development | Pre-deployment + continuous monitoring |
| How issues are fixed | Rewrite or refactor insecure code | Patch, upgrade, or replace components |
| Execution needed? | No (static) | No (metadata and component analysis) |
While SAST and SCA address different areas of risk, they are most effective when combined in a modern DevSecOps pipeline. Together, they provide full visibility into both code quality and the integrity of your software supply chain.
When used in CI/CD:
Using both ensures that development teams ship secure code while protecting the organization from dependency-based attacks, which remain one of the fastest-growing categories of application security breaches.
Organizations increasingly adopt SAST and SCA to support compliance frameworks and internal governance requirements. These tools help teams align with:
SAST ensures teams maintain consistent secure coding practices, while SCA demonstrates due diligence in managing vulnerabilities in third-party components — a growing requirement in many compliance audits.
Are you looking for ways to keep your first-party and open-source code secure for your clients and users? Kiuwan may have the tools you need. Request a free trial and see how you can strengthen your application security across every part of your codebase.
The main difference lies in the type of code each analyzes. SAST scans proprietary or first-party source code to detect logic flaws and insecure coding practices before the application runs. SCA examines open-source components and third-party libraries to identify known vulnerabilities and outdated dependencies.
Yes. Many teams integrate both SAST and SCA in their continuous integration and delivery workflows. Running SAST early in development helps prevent new vulnerabilities, while SCA continuously monitors open-source components for security issues as the software evolves.
SAST should be used from the earliest stages of coding through QA and pre-deployment testing. SCA scans should run throughout the lifecycle, including after release, to catch new vulnerabilities in open-source libraries or dependencies.
Both approaches support security frameworks such as OWASP, ISO 27001, and SOC 2. SAST validates secure coding practices, while SCA ensures that open-source components comply with vulnerability management requirements, helping maintain audit-ready documentation.
Look for tools that integrate with existing CI/CD platforms, provide detailed remediation guidance, minimize false positives, and offer continuous vulnerability monitoring. Unified solutions like Kiuwan can simplify management by combining both types of testing in a single interface.
