Here’s a clear and professional explanation of the three related concepts you asked about — all of which are critical parts of secure software development, especially in DevSecOps and open source software governance.

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🧩 1. What is Software Composition Analysis (SCA)?

Software Composition Analysis (SCA) is the automated process of identifying, managing, and securing third-party and open source components used in your software project.

🔍 Purpose:

• Detect known vulnerabilities (CVEs) in dependencies
• Identify license types and violations
• Track open source usage (OSS inventory)
• Ensure security, legal, and compliance in your codebase

🧪 What It Does:

Function	Description
📦 Detect dependencies	Parses package.json, pom.xml, etc.
🔐 Find vulnerabilities	Matches against CVE/NVD databases
⚖️ Check licenses	Verifies if licenses (GPL, MIT, etc.) violate policy
🧾 Inventory generation	Creates SBOM (Software Bill of Materials)
🔄 Continuous monitoring	Alerts when new CVEs are published

✅ Example Tools:

Snyk, OWASP Dependency-Check, Grype, Sonatype, Mend, Black Duck, FOSSA, Dependency-Track

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🕵️‍♂️ 2. What is Dependency Check?

Dependency checking refers to analyzing software dependencies (external libraries, packages, frameworks) to:

• Detect known vulnerabilities (CVEs)
• Alert on outdated or deprecated versions
• Determine if any risky components are being used

📌 It’s part of SCA, but specifically focuses on identifying security flaws in imported packages.

🔐 How it works:

• Extracts dependency list (e.g., from pom.xml, package-lock.json)
• Queries vulnerability databases (like NVD)
• Flags packages with known CVEs
• Suggests safer versions (if supported)

✅ Example Tools:

• OWASP Dependency-Check (open source)
• Grype (by Anchore)
• Snyk (commercial + free tier)
• GitHub Dependabot

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⚖️ 3. What is Open Source License Violation Check?

When you use open source software, you’re subject to its license terms (MIT, GPL, Apache, etc.).

Open Source License Checking ensures that:

• You don’t accidentally include a copyleft or viral license (like GPL) in proprietary software.
• Your use, distribution, or modification of code complies with the license.
• You meet legal obligations like attribution, redistribution rules, etc.

🚨 A “License Violation” Can Occur If You:

• Use GPL-licensed code in closed-source software
• Fail to provide attribution in MIT/BSD code
• Mix incompatible licenses in the same binary

✅ Tools That Detect License Violations:

• FOSSA (free/commercial)
• FOSSology (open source)
• Licensee (detects license from GitHub repos)
• Syft (shows license per package)
• Dependency-Track (shows license violations in SBOM)

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🔄 Relationship Between the Three

Area	SCA	Dependency Check	OSS License Check
Focus	Security + Legal + Inventory	Security (vulnerabilities)	Legal (licenses)
Input	Source code + package files	Dependencies (JAR, NPM, etc.)	LICENSE file, SPDX tags
Output	CVEs + License + SBOM	CVE alerts + upgrade paths	SPDX types, violation flags
Goal	Secure, compliant software	No vulnerable components	No legal risk from licenses

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📌 Real-World Example

Let’s say you’re building a JavaScript web app:

1. SCA scans package.json and tells you:
   • 1 high-risk CVE in lodash
   • 3 dependencies under MIT, 1 under GPLv3 (incompatible with your business)
2. Dependency Check tells you:
   • lodash@4.17.15 has CVE-2021-23337 → recommends upgrading to 4.17.21
3. License Checker tells you:
   • some-gpl-lib violates your license policy → you need to replace or isolate it

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✅ Final Recommendation

To achieve full open-source security and compliance, combine:

Task	Tool (Open Source Option)
CVE Detection	OWASP Dependency-Check / Grype
License Violation Check	FOSSology / Licensee / Syft
SBOM + Inventory	Syft / CycloneDX / Dependency-Track

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Here’s a detailed list of the Top 10 tools for Software Composition Analysis (SCA) — tools that analyze dependencies for:

• 🔐 Known vulnerabilities (CVEs)
• 🧾 Open source license compliance
• 📦 Outdated or risky libraries
• ⚖️ Policy violations and risk management

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🔟 Top 10 SCA Tools (Vulnerability, License & OSS Risk)

Tool Name	Best For	Key Features	License / CVEs	OSS License Check	Free Tier
Snyk	Modern apps (Node, Java, Python, etc.)	SCA + Fix PRs + Policy Gateways	✅	✅	✅
OWASP Dependency-Check	Open-source SCA scans	CVE scanning via NVD feeds	✅	Partial (SPDX tags)	✅
Mend (WhiteSource)	Enterprise-wide OSS risk mgmt	Compliance, security, reporting	✅	✅	❌
FOSSA	License compliance	Full SPDX license tree, CI/CD	✅	✅	✅ (limited)
Black Duck (Synopsys)	Enterprise-grade SCA	Code matching, CVEs, license risks	✅	✅	❌
GitHub Dependabot	GitHub native alerts & PRs	Auto-update CVE-prone libs	✅	❌	✅
Sonatype Nexus Lifecycle	Java Maven Central guardian	DevSecOps, BOM tracking, CVE watch	✅	✅	❌
SourceClear (Veracode)	DevSecOps SCA w/ security focus	Java, Node.js, Ruby support	✅	❌	❌
CycloneDX + Dependency-Track	SBOM generation + CVE trace	SBOM analysis and license alerts	✅	✅	✅
Licensee (GitHub project)	OSS license checking	GitHub-compatible SPDX detection	❌	✅	✅

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🧪 Tool-by-Tool Breakdown

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1. ✅ Snyk

• CLI + GitHub/GitLab integrations
• Real-time CVE scanning & fix suggestions
• License policies + developer PR fixes
• Supports: Java, Node, Python, Go, Docker

👉 snyk test + snyk monitor

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2. ✅ OWASP Dependency-Check

• Free & open-source
• Maps dependencies to CVEs (NVD DB)
• CLI or Maven/Gradle plugin
• HTML, XML, JSON output
• Java, .NET, Node.js, Python support

👉 dependency-check --scan ./ --format HTML

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3. 🏢 Mend (formerly WhiteSource)

• Deep license & CVE analysis
• Enterprise policies & audit trails
• IDE plugins, Docker images, CLI tools
• Strong commercial support

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4. 📜 FOSSA

• Dev-friendly license compliance tool
• Full SPDX license support
• Detects copyleft, GPL, permissive licenses
• CLI + CI/CD integrations

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5. 🏢 Black Duck (Synopsys)

• Legal compliance and full CVE map
• Detects unlicensed or unknown license code
• Ideal for regulated industries
• High precision in OSS detection

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6. 🔒 GitHub Dependabot

• Auto-pulls CVE patch PRs to GitHub projects
• GitHub-native integration
• Simple license check in repo insights (basic)
• Good for fast-moving teams

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7. 🛡️ Sonatype Nexus Lifecycle

• Deep OSS governance from Sonatype
• Maven Central-first intelligence
• Automatic quarantine of dangerous libs
• Excellent license policy enforcement

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8. 🔍 Veracode SourceClear

• Focus on runtime + reachable vulnerabilities
• Lightweight SCA + SAST
• Used in highly secure CI/CD

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9. 📦 CycloneDX + Dependency-Track

• SBOM generator (CycloneDX)
• Dependency-Track: CVE scanner for SBOMs
• Excellent for modern, multi-language apps
• Fully open source

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10. ⚖️ Licensee

• GitHub project to detect repo licenses
• Supports SPDX license tags
• CLI or GitHub Action usage

licensee detect .

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📊 Comparison Table: Summary View

Tool	CVE Scan	License Scan	SBOM Support	GitHub CI/CD	Free Tier
Snyk	✅	✅	✅ (partial)	✅	✅
OWASP Dep-Check	✅	Partial	❌	✅ (custom)	✅
Mend (WhiteSource)	✅	✅	✅	✅	❌
FOSSA	✅	✅	✅	✅	✅
Black Duck	✅	✅	✅	✅	❌
Dependabot	✅	❌	❌	✅	✅
Sonatype Lifecycle	✅	✅	✅	✅	❌
SourceClear	✅	❌	❌	✅	❌
CycloneDX + DTrack	✅	✅	✅	✅	✅
Licensee	❌	✅	❌	✅	✅

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🧠 Recommendation by Use Case

Use Case	Recommended Tool(s)
✅ Free + Open Source CVE Check	OWASP Dependency-Check, DTrack
✅ License Compliance for Legal	FOSSA, Black Duck, Sonatype
✅ Auto PR Fixing	Snyk, Dependabot
✅ SBOM Management	CycloneDX + Dependency-Track
✅ All-in-One Enterprise SCA	Mend, Black Duck, Sonatype

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Based on the search results, here are excellent 100% open source and free tool combinations that cover License Scanning, CVE Detection, and OSS analysis:

Comprehensive All-in-One Solutions

OWASP Dependency-Check is your best single-tool option as it provides both CVE detection and partial license scanning capabilities9. It’s a powerful open-source tool that detects vulnerabilities in project dependencies across a wide range of package managers and programming languages, with access to an extensive vulnerability database and seamless CI/CD integration.

Trivy offers another comprehensive approach, detecting vulnerabilities (CVEs) in open source software while also including license scanning features that present risk assessments for projects in your dependency tree. It’s particularly strong for containerized workloads, checking container images for OS packages, CVEs, misconfigurations, leaked secrets, and software licensing issues.

Specialized Tool Combinations

For License Scanning Focus:

• FOSSology – A Linux Foundation project providing comprehensive open-source license compliance software with command line, database, and web UI capabilities for license, copyright, and export control scans
• ScanCode – Specializes in analyzing licensing, copyright, and vulnerability information, with detailed license compliance checks and support for multiple programming languages
• LicenseFinder – Detects licenses in project code, compares against user-defined whitelists, and provides actionable reports

For CVE Detection Excellence:

• OpenVAS – Comprehensive vulnerability scanner with over 50,000 known Network Vulnerability Tests, supporting authenticated and unauthenticated protocols
• Retire.js – Specialized for JavaScript codebases, scanning for known vulnerabilities in third-party libraries with continuous database updates from CVE sources
• OSV-Scanner – Excellent for library dependency vulnerability detection in web and app environments

Recommended Tool Combinations

Combination 1: Maximum Coverage

• Trivy (CVE detection + license scanning)
• FOSSology (comprehensive license compliance)
• OpenVAS (network vulnerability scanning)

Combination 2: Developer-Friendly

• OWASP Dependency-Check (CVE detection + basic license scanning)
• ScanCode (detailed license analysis)
• Retire.js (JavaScript-specific vulnerabilities)

Combination 3: CI/CD Optimized

• Trivy (container and dependency scanning)
• LicenseFinder (license management with whitelist/blacklist)
• OSV-Scanner (library dependency vulnerabilities)

Additional Specialized Tools

Syft works excellently for generating Software Bill of Materials (SBOM) with license information, particularly when paired with Grype for vulnerability scanning10. Ninka provides rapid license identification for quick scans11, while Code Janitor from The Linux Foundation helps evaluate source code for open source license compliance1.

All these tools are completely free, open source, and can be integrated into CI/CD pipelines. The combination you choose depends on your specific technology stack, with JavaScript projects benefiting from Retire.js, containerized applications from Trivy, and comprehensive enterprise needs from FOSSology paired with OpenVAS.