Maven Dependency Audit Skill

Audit Maven dependencies for updates, vulnerabilities, and conflicts.

When to Use

• User says "check dependencies" / "audit dependencies" / "outdated dependencies"

• Before a release

• Regular maintenance (monthly recommended)

• After security advisory

Audit Workflow

• Check for updates - Find outdated dependencies

• Analyze tree - Find conflicts and duplicates

• Security scan - Check for vulnerabilities

• Report - Summary with prioritized actions

1. Check for Outdated Dependencies

Command

mvn versions:display-dependency-updates

Output Analysis

[INFO] The following dependencies in Dependencies have newer versions: [INFO] org.slf4j:slf4j-api ......................... 1.7.36 -> 2.0.9 [INFO] com.fasterxml.jackson.core:jackson-databind . 2.14.0 -> 2.16.1 [INFO] org.junit.jupiter:junit-jupiter ............. 5.9.0 -> 5.10.1

Categorize Updates

Category Criteria Action

Security CVE fix in newer version Update ASAP

Major x.0.0 change Review changelog, test thoroughly

Minor x.y.0 change Usually safe, test

Patch x.y.z change Safe, minimal testing

Check Plugin Updates Too

mvn versions:display-plugin-updates

2. Analyze Dependency Tree

Full Tree

mvn dependency:tree

Filter for Specific Dependency

mvn dependency:tree -Dincludes=org.slf4j

Find Conflicts

Look for:

[INFO] +- com.example:module-a:jar:1.0:compile [INFO] | - org.slf4j:slf4j-api:jar:1.7.36:compile [INFO] +- com.example:module-b:jar:1.0:compile [INFO] | - org.slf4j:slf4j-api:jar:2.0.9:compile (omitted for conflict)

Flags:

• (omitted for conflict)

• Version conflict resolved by Maven

• (omitted for duplicate)

• Same version, no issue

• Multiple versions of same library - Potential runtime issues

Analyze Unused Dependencies

mvn dependency:analyze

Output:

[WARNING] Used undeclared dependencies found: [WARNING] org.slf4j:slf4j-api:jar:2.0.9:compile [WARNING] Unused declared dependencies found: [WARNING] commons-io:commons-io:jar:2.11.0:compile

3. Security Vulnerability Scan

Option A: OWASP Dependency-Check (Recommended)

Add to pom.xml:

<plugin> <groupId>org.owasp</groupId> <artifactId>dependency-check-maven</artifactId> <version>9.0.7</version> </plugin>

Run:

mvn dependency-check:check

Output: HTML report in target/dependency-check-report.html

Option B: Maven Dependency Plugin

mvn dependency:analyze-report

Option C: GitHub Dependabot

If using GitHub, enable Dependabot alerts in repository settings.

Severity Levels

CVSS Score Severity Action

9.0 - 10.0 Critical Update immediately

7.0 - 8.9 High Update within days

4.0 - 6.9 Medium Update within weeks

0.1 - 3.9 Low Update at convenience

4. Generate Audit Report

Output Format

Dependency Audit Report

Project: {project-name} Date: {date} Total Dependencies: {count}

Security Issues

Outdated Dependencies

Major Updates (Review Required)

Minor/Patch Updates (Safe)

Conflicts Detected

• slf4j-api: 1.7.36 vs 2.0.9 (resolved to 2.0.9)

Unused Dependencies

• commons-io:commons-io:2.11.0 (consider removing)

Recommendations

1. Immediate: Update log4j-core to fix CVE-2021-44228
2. This sprint: Update minor/patch versions
3. Plan: Evaluate slf4j 2.x migration

Common Scenarios

Scenario: Check Before Release

Quick check

mvn versions:display-dependency-updates -q

Full audit

mvn versions:display-dependency-updates &&
mvn dependency:analyze &&
mvn dependency-check:check

Scenario: Find Why Dependency is Included

mvn dependency:tree -Dincludes=commons-logging

Scenario: Force Specific Version (Resolve Conflict)

<dependencyManagement> <dependencies> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>2.0.9</version> </dependency> </dependencies> </dependencyManagement>

Scenario: Exclude Transitive Dependency

<dependency> <groupId>com.example</groupId> <artifactId>some-library</artifactId> <version>1.0</version> <exclusions> <exclusion> <groupId>commons-logging</groupId> <artifactId>commons-logging</artifactId> </exclusion> </exclusions> </dependency>

Token Optimization

• Use -q (quiet) flag for less verbose output

• Filter with -Dincludes=groupId:artifactId when looking for specific deps

• Run commands separately and summarize findings

• Don't paste entire dependency tree - summarize conflicts

Quick Commands Reference

Task Command

Outdated deps mvn versions:display-dependency-updates

Outdated plugins mvn versions:display-plugin-updates

Dependency tree mvn dependency:tree

Find specific dep mvn dependency:tree -Dincludes=groupId

Unused deps mvn dependency:analyze

Security scan mvn dependency-check:check

Update versions mvn versions:use-latest-releases

Update snapshots mvn versions:use-latest-snapshots

Update Strategies

Conservative (Recommended for Production)

• Update patch versions freely

• Update minor versions with basic testing

• Major versions require migration plan

Aggressive (For Active Development)

Update all to latest (use with caution!)

mvn versions:use-latest-releases mvn versions:commit # or versions:revert

Selective

Update specific dependency

mvn versions:use-latest-versions -Dincludes=org.junit.jupiter