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Software Composition Analysis (SCA)

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Sonar

Research & Development

TL;DR overview

  • Software Composition Analysis (SCA) is an automated process that identifies, analyzes, and manages open source components within applications to detect security vulnerabilities, license compliance issues, and outdated dependencies.
  • Modern applications consist of 80–90% open source code, and supply chain attacks increased by 300% in 2021–2022, making SCA an essential practice for managing the risks associated with third-party dependencies.
  • SCA tools work by scanning project manifests and build configurations, cross-referencing components against vulnerability databases like the NVD and CVE, checking license compliance, and generating a Software Bill of Materials (SBOM).
  • SonarQube integrates SCA capabilities to provide continuous scanning of open source components alongside first-party code analysis, supporting unified code quality and security workflows.

Imagine your software as a complex puzzle, where each piece comes from different sources. What if one piece is flawed or broken? This is the challenge developers face when using open-source components. A single vulnerability can compromise an entire application, as seen with the infamous Log4Shell incident. This is where Software Composition Analysis (SCA) comes in useful. SCA acts as your detective, uncovering hidden risks in your software's supply chain. 

What is Software Composition Analysis (SCA) in Software Development? 

Software Composition Analysis (SCA) is an automated process used in software development to identify, analyze, and manage open-source components within an application. Modern software relies heavily on open-source libraries and third-party dependencies (libraries), making them part of a complex software supply chain. The software supply chain has become a prime target for attackers, as compromising a single component can affect thousands of downstream applications. 

This is why SCA has become an essential part of modern software security practices.  It is crucial to understand the security, licensing, and compliance risks associated with the use of these components. SCA tools scan codebases to detect vulnerabilities, outdated dependencies, and potential legal issues arising from open-source license violations. By integrating SCA into the software development lifecycle (SDLC), development teams can proactively mitigate risks, ensure compliance with industry regulations, and enhance overall application security.

Let's explore the key elements of SCA:

Vulnerability Detection (CVE)

SCA tools continuously scan for Common Vulnerabilities and Exposures (CVEs) in your dependencies. These vulnerabilities are identified by unique CVE IDs and are stored in public databases like the National Vulnerability Database (NVD). When a vulnerability is detected, SCA tools provide detailed information about:

  • The severity level (CVSS score)
  • Affected versions
  • Available patches or fixes
  • Potential exploit scenarios
  • Remediation steps

License Compliance

SCA tools help manage the complex world of open-source licensing by:

  • Identifying all licenses in use
  • Flagging incompatible licenses
  • Ensuring compliance with open-source license terms
  • Maintaining license inventories
  • Generating compliance reports for legal teams

Dependency Management

This aspect involves:

  • Comprehensive dependency trees to identify direct and transitive dependencies
  • Suggesting version updates
  • Monitoring dependency health and maintenance status

Software Bill of Materials (SBOM)

An SBOM is a formal, machine-readable inventory of software components and dependencies. It includes:

  • Component names and versions
  • Licensing information
  • Known vulnerabilities
  • Component relationships and dependencies
  • Origin and supplier information

Why is SCA important?

Software Composition Analysis (SCA) is critical in modern software development because it helps organizations identify and manage the risks associated with open-source components, which make up the majority of today's applications. SCA's importance stems from several critical factors:

  1. Risk Management:
    • 80-90% of modern applications consist of open-source code
    • Supply chain attacks increased by 300% in 2021-2022
    • Average time to detect a vulnerability is reduced from months to minutes
  2. Compliance Requirements:
    • Many regulations (GDPR, HIPAA, PCI DSS) require dependency tracking
    • Executive Order 14028 mandates SBOM for federal suppliers
    • Industry standards increasingly require component transparency

With the increasing reliance on open-source software, ensuring security, compliance, and risk mitigation has become a top priority for development teams. SCA provides automated scanning and analysis of third-party dependencies, ensuring that software remains secure, compliant, and resilient against cyber threats.

How does SCA work? 

SCA works by analyzing software dependencies, including direct and transitive (indirect) dependencies, to identify known security vulnerabilities listed in public vulnerability databases like the Common Vulnerabilities and Exposures (CVE) database, the National Vulnerability Database (NVD), and proprietary security databases maintained by SCA vendors. 

When vulnerabilities are found, SCA tools provide actionable insights, such as recommended updates, patch availability, and severity ratings, helping developers remediate security issues efficiently. Additionally, SCA ensures license compliance by detecting open-source licenses like GPL, MIT, Apache, and BSD, which can have legal implications if improperly used in proprietary software.

SCA operates through several mechanisms:

  1. Discovery Phase:
    • Scans project manifests (package.json, pom.xml, requirements.txt)
    • Analyzes build configurations
    • Identifies binary and source code components
  2. Analysis Phase:
    • Cross-references components with vulnerability databases
    • Checks license compliance
    • Validates version compatibility
    • Assesses component quality and maintenance status
  3. Monitoring Phase:
    • Continuous scanning for new vulnerabilities
    • Real-time alerts for security issues
    • Update notifications
    • Dependency drift detection

What are the benefits of SCA?

Software Composition Analysis (SCA) offers several critical benefits to software development, making it an indispensable tool for modern development teams. 

  • Reduced Security Risks
  • Development Efficiency
  • Lower Costs
  • Better Code Quality
  • Legal Compliance
  • Enhanced Trust

Reduced Security Risks

  • Decreased vulnerability exposure, and exposure time
  • Better license compliance
  • Improved supply chain visibility

Development Efficiency

  • Faster component selection
  • Automated updates
  • Reduced manual security reviews

Lower Costs

  • Reduced incident response costs
  • Lower maintenance overhead
  • Better resource allocation

Legal Compliance

SCA tools ensure that organizations comply with the various licenses of the open-source components they use. By identifying and cataloging these licenses, they help avoid legal risks associated with the misuse of open-source software.

Effective Risk Management

SCA provides insights into the dependencies used within a project, enabling organizations to manage and mitigate risks effectively. This includes tracking deprecated or outdated libraries and suggesting safer, up-to-date alternatives.

Continuous Quality Assurance

Integration of SCA tools with Continuous Integration/Continuous Deployment (CI/CD) pipelines allows for continuous feedback on code quality. This integration helps maintain high coding standards and minimizes the likelihood of introducing errors or vulnerabilities into the codebase.

Operational Efficiency

SCA automates the identification and remediation of vulnerabilities in open-source components, streamlining the management process. This automation leads to increased operational efficiency, allowing development teams to focus on other critical tasks.

Comprehensive Dependency Management

SCA provides a holistic view of all third-party code used within a project. This comprehensive view enables developers and managers to understand the associated risks and make informed decisions to enhance the security and reliability of their software.

How does SCA improve security?

SCA enhances security through multiple mechanisms:

  1. Proactive Defense:
    • Early vulnerability detection
    • Automated security updates
    • Risk-based prioritization
  2. Supply Chain Security:
    • Component verification
    • Origin tracking
    • Malicious package detection
  3. Continuous Monitoring:
    • Real-time vulnerability alerts
    • Dependency health monitoring
    • Security metric tracking

What is the difference between SCA and SAST?

SCA

SAST

Analyzes third-party and open-source components

Analyzes your custom-written source code

Focuses on known vulnerabilities in dependencies

Looks for potential security issues in code logic

Checks license compliance

Identifies coding best practices violations

Works with package managers and dependency files

Works directly with source code

Comparison table of SCA and SAST

SCA and SonarQube

SonarQube Advanced Security brings together SCA and advanced SAST, building on core security features like SAST, secrets detection, taint analysis, and IaC scanning. It analyzes your software supply chain, uncovers vulnerabilities, ensures license compliance, and proactively secures your codebase—reducing risks from third-party open source dependencies. With comprehensive coverage for first-party, AI-generated, and third-party code, SonarQube delivers end-to-end protection for your entire codebase.

Learn more about our security solution. 

SCA FAQs

What is SCA reachability analysis?

Reachability analysis determines whether your application actually calls the vulnerable part of an open source dependency. A library may contain a known vulnerability, but the risk is low if your code never reaches the affected function or code path. SCA tools with reachability analysis trace how your code uses each dependency and mark findings as reachable or unreachable. This helps teams focus on vulnerabilities that can realistically be exploited.

How do you know if a CVE is exploitable?

A CVE is more likely to be exploitable when evidence shows attackers can use it in practice, not just when its severity score is high. Check whether it appears in a known exploited vulnerabilities catalog, whether public exploit code exists, and whether a scoring model such as EPSS rates exploitation as likely. Then confirm that your application reaches the vulnerable code and that your configuration exposes it. Combining severity, exploit evidence, and context gives a more reliable priority than CVSS alone.

What is a transitive dependency and how do you fix a vulnerable one?

A transitive dependency is a library that your project needs only because one of your direct dependencies uses it. Most dependency trees contain far more transitive packages than direct ones, so many vulnerabilities arrive this way. To fix one, first update the direct dependency that pulls it in, since a newer release often upgrades the nested package. If no update exists, override or pin the safe version using your build tool’s dependency management features, or exclude the package if it is not needed.

How do you integrate SCA into CI/CD pipelines?

You integrate SCA by adding an automated dependency scan as a step that runs on every pull request and build. The scan reads manifests and lockfiles, matches components against vulnerability and license data, and reports findings in the pull request or build log. Set policy thresholds, such as blocking merges for critical vulnerabilities or disallowed licenses, so the pipeline enforces your standards. Also schedule recurring scans of the main branch, because new vulnerabilities are published for code that has not changed.

Is an SBOM legally required?

It depends on where you sell software and who your customers are. The EU Cyber Resilience Act requires manufacturers to keep an SBOM as part of their technical documentation. In the United States, federal procurement rules that grew out of Executive Order 14028 have asked software suppliers for SBOMs or related attestations, and requirements continue to evolve. Regulated industries and enterprise customers also increasingly request SBOMs in contracts, so many teams generate them even when no law applies directly.

How does an SBOM help with zero-day vulnerabilities?

An SBOM does not prevent zero-day attacks, but it lets you respond much faster when a new vulnerability is disclosed. When a flaw like Log4Shell appears, teams with current SBOMs can search them to see which applications and versions include the affected component. Without an SBOM, that search can take days of manual investigation across repositories and vendors. Faster identification shortens the time between disclosure and patching.

What are the limitations of SCA?

SCA mainly finds known vulnerabilities and license issues in third-party components, so it has clear boundaries. It cannot detect unknown flaws in a library before they are disclosed, and it does not find security problems in your own code, which is the role of SAST and code review. Results depend on the quality of vulnerability data and on accurate dependency resolution, and copied or vendored code can be missed. Teams also see noise from findings that are not reachable, so prioritization is essential.

Does AI-generated code create software composition risks?

Yes, AI-generated code can introduce risky dependencies. Coding assistants may suggest outdated library versions, packages with known vulnerabilities, or package names that do not exist, which attackers can register with malicious code. They can also reproduce code that carries license obligations without noting them. Scan developer-written and AI-generated code with the same SCA checks, and review every new dependency before it merges.

How often should you run SCA scans?

Run SCA scans on every pull request and build, and keep monitoring after release. Scans at commit time catch risky dependencies before they merge. Continuous or scheduled monitoring matters just as much, because new vulnerabilities and license findings are published for versions you already use. Many teams combine pull request checks with daily monitoring of production branches and alerts when a new advisory affects a component.

How does SCA relate to software supply chain security?

SCA is one important part of software supply chain security, focused on the open source and third-party components you consume. It gives you visibility into what is in your software, which versions you run, and which known risks and licenses apply. Supply chain security is broader. It also covers build integrity, code signing, provenance, CI/CD pipeline protection, secrets management, and detection of malicious packages. Most organizations need SCA as the foundation and add those controls around it.