Open-Source SCA Tools

Software Composition Analysis (SCA) tools scan your application dependencies for known vulnerabilities, license risks, and outdated components. Open-source SCA tools give you this capability without vendor lock-in or license fees.

Why choose open-source SCA tools?

The core job of an SCA tool is straightforward: read your dependency manifests, resolve the full tree, and check every component against vulnerability databases. Open-source tools do this well. They pull from the same databases that commercial tools use – NVD, GitHub Advisory Database, OSV – and they run in the same CI/CD pipelines.

The cost argument is obvious but worth stating. Commercial SCA platforms charge per-developer or per-project fees that can reach five or six figures annually. For startups, small teams, and open-source projects, that budget simply does not exist. Open-source SCA removes the financial barrier entirely.

Beyond cost, open-source SCA tools offer transparency. You can inspect exactly how vulnerability matching works, contribute rules, and customize behavior. When a tool produces a false positive, you can trace the logic and understand why. With commercial tools, the matching engine is a black box.

CI/CD flexibility is another advantage. Every open-source SCA tool on this list ships as a standalone CLI binary. No agent installations, no SaaS accounts, no phone calls with sales engineers. Install it, point it at your code, and get results. This makes open-source tools ideal for air-gapped environments, self-hosted CI systems, and teams that want full control over their toolchain.

The open-source SCA ecosystem has come a long way. Trivy now has 32,000+ GitHub stars and scans containers, filesystems, and IaC. Grype introduced EPSS-based risk scoring. OSV-Scanner ships with guided remediation. These are not toy tools filling a gap until you can afford a commercial license. For many teams, they are the final answer.

Top open-source SCA tools

1. Trivy

Trivy is the most-starred open-source security scanner on GitHub with 32,200+ stars. Built by Aqua Security and released under Apache 2.0, it scans container images, filesystems, git repositories, VM images, and Kubernetes clusters for vulnerabilities, misconfigurations, secrets, and license issues.

What makes Trivy stand out for SCA is its breadth. A single trivy fs . command scans your dependency lock files across Go, Java, Node.js, Python, Ruby, Rust, PHP, .NET, Dart, Elixir, and Swift. It also generates SBOMs in CycloneDX and SPDX formats, so you get inventory and vulnerability scanning from one tool.

Trivy’s vulnerability database covers NVD, GitHub Advisories, and distribution-specific feeds (Alpine, Debian, Ubuntu, RHEL, Amazon Linux). The database downloads automatically and updates with each scan.

Best for: Teams that want a single tool covering dependency scanning, container scanning, IaC checks, and SBOM generation.

2. Grype

Grype is Anchore’s open-source vulnerability scanner with 11,500 GitHub stars. Where Trivy tries to do everything, Grype focuses on one thing: matching packages against vulnerability databases with high accuracy.

Grype’s standout feature is its risk scoring engine. Each finding gets a composite score from 0 to 10 that combines CVSS severity, EPSS exploit probability (the 30-day likelihood of exploitation), and KEV catalog status (whether CISA lists it as actively exploited). This scoring helps teams prioritize what to fix first instead of drowning in a flat list sorted by CVSS alone.

Grype covers 20+ language ecosystems and all major Linux distributions. It accepts container images, filesystem directories, and SBOM files (CycloneDX, SPDX, Syft JSON) as input. OpenVEX support lets you suppress findings your security team has already assessed.

Best for: Teams that want a fast, focused vulnerability scanner with advanced risk scoring and SBOM-first workflows.

3. OWASP Dependency-Check

OWASP Dependency-Check is the elder statesman of open-source SCA. As an OWASP Flagship Project with 7,400 GitHub stars and 290+ contributors, it has been a standard in enterprise Java shops for over a decade. The current version is 12.2.0.

Dependency-Check identifies vulnerabilities using CPE (Common Platform Enumeration) matching against the NVD. It has native plugins for Maven, Gradle, and Ant with failBuildOnCVSS threshold gating built in. Beyond Java, it supports npm, pip, Ruby Bundler, Go modules, and NuGet.

The CPE matching approach produces more false positives than ecosystem-specific matching (which Grype and Trivy use), but it also catches vulnerabilities that ecosystem-specific tools sometimes miss. An NVD API key is strongly recommended to avoid rate-limited database updates.

Best for: Enterprise Java teams with Maven or Gradle builds that need a proven, OWASP-backed scanner with native build tool integration.

4. Syft

Syft is Anchore’s open-source SBOM generation tool with 8,400 GitHub stars. It does not scan for vulnerabilities itself. Instead, it catalogs every software component in your container images, filesystems, and archives, outputting SBOMs in SPDX and CycloneDX formats.

Syft auto-detects dozens of package ecosystems – Alpine, Debian, RPM, npm, pip, Maven, Go modules, Ruby gems, Rust crates, PHP Composer, .NET NuGet, and more. It runs entirely offline with no cloud dependencies or API calls.

The intended workflow is to pair Syft with Grype: generate the SBOM once with Syft, then scan it with Grype whenever the vulnerability database updates. This separation lets you cache SBOMs and avoid redundant image analysis. Syft also supports signed SBOM attestations using the in-toto specification for supply chain verification.

Best for: Teams that need SBOM generation for compliance (Executive Order 14028, EU CRA) or want a Syft + Grype pipeline for supply chain visibility.

5. OSV-Scanner

OSV-Scanner is Google’s free vulnerability scanner, querying the OSV.dev database – the largest aggregated source of open-source vulnerability data, pulling from 30+ ecosystem-specific sources. It has 8,300+ GitHub stars and is written in Go.

The killer feature is guided remediation. Instead of dumping a CVE list and walking away, OSV-Scanner V2 analyzes your dependency graph and recommends the minimum set of upgrades, ranked by severity, dependency depth, and return on investment. Guided remediation currently supports npm and Maven, with more ecosystems planned.

OSV-Scanner also does layer-aware container image scanning for Alpine, Debian, and Ubuntu images. It identifies which layer introduced each package and filters vulnerabilities unlikely to affect the running container. Interactive HTML reports make results accessible to non-terminal users.

Best for: Teams that want guided remediation advice, not just a vulnerability list. Especially useful for JavaScript and Java projects.

6. npm audit

npm audit ships with every Node.js installation. Run npm audit in any project directory and it checks your dependency tree against the GitHub Advisory Database. No installation, no configuration, no account required.

For JavaScript teams, npm audit is the zero-friction starting point. It catches known vulnerabilities in both direct and transitive dependencies and suggests upgrade paths. The npm audit fix command applies safe upgrades automatically. The --production flag limits scanning to production dependencies, filtering out devDependencies.

The limitation is scope: npm audit only covers the npm ecosystem. It does not scan container images, generate SBOMs, or support non-JavaScript dependencies. For polyglot projects, combine it with a broader tool like Trivy or Grype.

Best for: JavaScript/Node.js teams that want zero-setup dependency scanning as part of their existing npm workflow.

7. pip-audit

pip-audit is a Python dependency scanner maintained by the Python Packaging Authority (PyPA) and Trail of Bits. It checks installed packages against the OSV database and PyPI’s vulnerability feed. Install it with pip install pip-audit and run pip-audit in your project directory.

pip-audit resolves the full dependency tree using pip’s resolver, catching vulnerabilities in transitive dependencies that manual checks miss. It supports requirements.txt, pyproject.toml, and installed package environments. Output formats include JSON, CycloneDX, and Markdown.

Unlike OWASP Dependency-Check’s Python support (which uses NVD/CPE matching), pip-audit uses ecosystem-specific matching through the OSV database, resulting in fewer false positives for Python packages.

Best for: Python teams that want a lightweight, PyPA-maintained scanner with low false positive rates.

8. Retire.js

Retire.js scans JavaScript libraries for known vulnerabilities, focusing on both npm packages and JavaScript files loaded in web applications. It has a Burp Suite plugin, a command-line scanner, a Chrome extension, and a Grunt plugin.

What sets Retire.js apart from npm audit is its ability to scan JavaScript files on disk or in web pages, not just packages in node_modules. It identifies vulnerable jQuery versions included via CDN, outdated Bootstrap copies, and other client-side libraries that npm audit never sees.

OWASP Dependency-Check bundles Retire.js data as one of its vulnerability sources, so if you already run Dependency-Check, you get some of this coverage. Standalone Retire.js is useful when you need to scan web applications for client-side library vulnerabilities specifically.

Best for: Web application teams with client-side JavaScript dependencies loaded via CDN or copied into the codebase rather than managed through npm.

9. Bundler-Audit

Bundler-Audit scans Ruby applications for vulnerable gem versions. Run bundle audit check against your Gemfile.lock and it reports any gems with known CVEs from the Ruby Advisory Database.

The tool is minimal and focused. It checks your locked gem versions against a curated advisory database, reports findings, and exits. No configuration needed. Integrates into CI pipelines as a single command. Update the advisory database with bundle audit update.

For Rails teams already using Bundler, this is the path of least resistance for dependency vulnerability scanning. Pair it with Brakeman for Rails-specific SAST coverage.

Best for: Ruby on Rails teams using Bundler for dependency management.

10. Cargo-audit

Cargo-audit is the Rust equivalent of Bundler-Audit. It scans Cargo.lock files against the RustSec Advisory Database, reporting known vulnerabilities in Rust crate dependencies.

Run cargo audit in any Rust project directory. The tool checks both direct and transitive dependencies and reports CVEs, severity levels, and patched versions. It also detects yanked crates and unmaintained dependencies, adding a supply chain hygiene layer beyond pure vulnerability matching.

The Rust ecosystem has embraced cargo-audit as a standard part of CI pipelines. Most Rust projects run it alongside cargo clippy and cargo test as part of their pre-merge checks.

Best for: Rust teams that want crate dependency scanning integrated into their Cargo workflow.

11. Safety

Safety is a Python dependency scanner that checks packages against the Safety DB (maintained by SafetyCLI, formerly PyUp). Run safety check -r requirements.txt to scan your Python dependencies.

Safety’s database includes CVE data plus additional advisories that SafetyCLI curates. The free version provides basic vulnerability scanning, while the commercial version adds more frequent database updates, CI/CD integration features, and policy management.

For Python-only teams choosing between Safety and pip-audit, pip-audit has the advantage of being maintained by PyPA with OSV database access. Safety’s curated database can catch some advisories earlier, but the free tier has update frequency limitations.

Best for: Python teams already familiar with Safety’s workflow, or those wanting a second opinion alongside pip-audit.

12. Dependency-Track

Dependency-Track is not a scanner – it is a continuous monitoring platform. This OWASP Flagship Project (3,600 GitHub stars) ingests SBOMs in CycloneDX or SPDX format and continuously correlates every component against NVD, GitHub Advisories, Sonatype OSS Index, and OSV.

The difference from every other tool on this list: Dependency-Track does not run at build time and produce a one-time report. It maintains a persistent inventory of components across your entire application portfolio. When a new CVE is published, it immediately flags every affected project without requiring a rescan.

Deploy it with Docker Compose, upload SBOMs from your CI pipelines (generated by Syft, Trivy, or any CycloneDX/SPDX producer), and you get portfolio-wide risk dashboards, policy enforcement, and alerting. The API-first architecture integrates with Slack, Teams, Jira, and custom webhooks.

Best for: Organizations managing 10+ applications that need continuous component monitoring beyond point-in-time CI scans.

Feature comparison

How to choose the right tool

The decision depends on three factors: your language stack, whether you scan containers, and how many applications you manage.

Single-language teams

If you write exclusively in one language, start with the ecosystem-specific tool. Ruby teams use Bundler-Audit. Rust teams use Cargo-audit. Python teams use pip-audit. JavaScript teams use npm audit. These tools are thin, fast, and produce fewer false positives than general-purpose scanners because they understand ecosystem-specific package naming and versioning.

Polyglot or container-heavy teams

If your stack spans multiple languages or you ship container images, Trivy is the default starting point. One binary scans your dependency manifests, container images, and IaC configs. You get vulnerability detection, SBOM generation, and misconfiguration scanning without installing three separate tools.

For teams that want more focused vulnerability matching with better risk scoring, Grype paired with Syft is the alternative. Syft handles SBOM generation, Grype handles vulnerability scanning with EPSS and KEV-based prioritization. This two-tool approach gives you more control over each step.

Enterprise Java shops

If you run Maven or Gradle builds in Jenkins, OWASP Dependency-Check is the path of least resistance. Its native build tool plugins, OWASP branding, and decade-long track record make it an easy sell to management and audit teams. Pair it with Dependency-Track for continuous monitoring.

Multiple applications at scale

Once you manage more than a handful of applications, point-in-time scanning is not enough. A new CVE disclosed on Tuesday affects code you deployed last month. Dependency-Track adds the continuous monitoring layer: upload SBOMs from every CI build, and the platform alerts you to new vulnerabilities across your entire portfolio.

CI/CD integration patterns

GitHub Actions

Most open-source SCA tools have official or community-maintained GitHub Actions. Here is a minimal Trivy example:

- name: Scan dependencies
  uses: aquasecurity/trivy-action@master
  with:
    scan-type: 'fs'
    scan-ref: '.'
    severity: 'HIGH,CRITICAL'
    exit-code: '1'

For Grype, use the official Anchore scan action:

- name: Scan with Grype
  uses: anchore/scan-action@v7
  with:
    path: '.'
    fail-build: true
    severity-cutoff: high

GitLab CI

Add a security stage to your .gitlab-ci.yml:

sca-scan:
  image: aquasec/trivy:latest
  stage: security
  script:
    - trivy fs --exit-code 1 --severity HIGH,CRITICAL .
  allow_failure: false

Pre-commit hooks

Catch vulnerable dependencies before they reach CI. Add a pre-commit hook that runs your SCA tool against lock files:

#!/bin/sh
# .git/hooks/pre-commit
trivy fs --severity CRITICAL --exit-code 1 --quiet .

For JavaScript projects, npm audit can run as part of a Husky pre-commit hook with zero additional tooling.

Limitations vs commercial alternatives

Open-source SCA tools are strong on vulnerability detection. They fall short in areas that require significant engineering investment beyond database matching.

No reachability analysis. Commercial tools like Endor Labs and Snyk analyze whether your code actually calls the vulnerable function in a dependency. This cuts alert volume by 70-90%. Open-source tools flag every vulnerable component regardless of whether the vulnerability is reachable from your code paths.

Limited fix suggestions. Dependabot and Renovate open automated pull requests that bump vulnerable dependencies. Most open-source SCA scanners report the vulnerability and stop. You figure out the upgrade path yourself. OSV-Scanner’s guided remediation is a step forward, but it currently covers only npm and Maven.

Manual license compliance. Trivy flags licenses, Syft includes them in SBOMs, but neither provides the policy engine that Mend or Black Duck offer for automated license compliance management. If your legal team needs a full license audit with policy enforcement, open-source tools create the raw data but not the workflow.

No unified dashboard. Each open-source tool produces its own report format. Dependency-Track adds a centralized view, but it requires infrastructure to host and maintain. Commercial platforms like Snyk and Endor Labs provide a single pane of glass out of the box.

No dedicated support. When a tool produces an unexpected result, your options are GitHub Issues, community Slack channels, and reading source code. Commercial vendors provide support engineers, SLA-backed response times, and custom rule development.

For teams that hit these limitations, the SCA tools category covers commercial options in detail. Our Snyk vs Dependabot and Trivy vs Grype comparisons provide head-to-head analysis of specific tools.

FAQ

Frequently Asked Questions