Claude Code Security Audit: Find & Fix OWASP Vulnerabilities in Minutes

Last week, a solo founder ran /security-audit on his SaaS codebase. Claude Code found 23 vulnerabilities in 47 minutes — including an SQL injection that had been live for 8 months. A professional audit would have cost him $15K and taken 3 weeks. He fixed everything that afternoon.

This guide shows you the exact same process. You’ll get copy-paste commands for scanning OWASP vulnerabilities, weak auth, exposed secrets, and dependency CVEs — all using Claude Code’s built-in security skills.

TL;DR: Run /security-audit in Claude Code to scan your entire codebase. It checks for OWASP Top 10 vulnerabilities, reviews dependencies for CVEs, audits auth/config, and generates a prioritized fix list. Get the security audit skill free →

What you’ll need: Claude Code installed (setup guide if not). If you’re still writing security prompts from scratch, read why reusable skills beat one-off prompts first — it’ll save you hours.

What an AI-Powered Security Audit Covers (5 Phases)

Here’s what Claude Code checks — and what most teams miss until it’s too late:

1. Static Code Analysis

• SQL injection vulnerabilities
• Cross-site scripting (XSS) risks
• Insecure deserialization
• Hardcoded credentials
• Weak cryptography
• Missing input validation

2. Dependency Analysis

• Known CVEs in your packages
• Outdated libraries
• License compliance issues
• Dependency bloat

3. Configuration Review

• Exposed environment variables
• Weak authentication setup
• Missing encryption
• Overly permissive access controls
• Misconfigured cloud resources

4. Architecture Review

• Data flow security
• API security
• Authentication/authorization patterns
• Session management
• CSRF protection

5. Compliance Checks

• GDPR data handling
• PCI DSS for payment processing
• SOC 2 readiness
• HIPAA requirements
• Industry-specific standards

Want to run this audit right now? The free Claude Skills 360 starter kit includes the /security-audit skill — no credit card, 2-minute install. It covers all 5 phases above in a single command.

Setting Up Your Security Audit Agent

Step 1: Prepare Your Codebase

# Export your code structure (not node_modules)
find . -type f \( -name "*.js" -o -name "*.ts" -o -name "*.jsx" -o -name "*.tsx" -o -name "*.py" \) -not -path "*/node_modules/*" -not -path "*/.git/*" > code-manifest.txt

# Count files
wc -l code-manifest.txt  # Should be manageable number

Step 2: Create a Security Audit Profile

# Security Audit Profile

## Application Details
- Name: [Your App]
- Type: Web / Mobile / API / SaaS
- Stack: Next.js + Node.js + PostgreSQL
- Data Sensitivity: High (stores payment info, PII)
- Users: 5,000+ active users
- Compliance: SOC 2, GDPR, PCI DSS

## Attack Surface
- Web: https://app.example.com
- API: https://api.example.com/v1
- Mobile: iOS and Android apps
- Third-party integrations: Stripe, SendGrid, AWS

## Known Constraints
- Legacy code in /legacy/ directory
- Payment processing via Stripe (PCI compliance delegated)
- Authentication: NextAuth with OAuth providers
- Deployment: AWS ECS + RDS

## Previous Issues
- SQL injection in user search (fixed v1.3)
- XSS in comments (fixed v1.2)
- Exposed API keys (fixed v1.1)

## Audit Goals
1. Find unknown vulnerabilities
2. Assess compliance readiness
3. Prioritize remediation
4. Document security controls

Step 3: Invoke the Security Audit Agent

/security-audit-agent

Run a comprehensive audit on my codebase:
1. Scan for OWASP Top 10 vulnerabilities
2. Check all dependencies for CVEs
3. Review authentication/authorization
4. Assess data handling practices
5. Check compliance with SOC 2
6. Generate risk-rated findings
7. Provide remediation steps

Use this profile: [paste your security audit profile]

Focus on critical and high-risk issues first.

Claude Code will systematically:

1. Read your code
2. Analyze each file for vulnerabilities
3. Check dependencies
4. Cross-reference against known vulnerabilities
5. Generate findings with risk scores
6. Suggest fixes

OWASP Top 10 and What to Look For

Here’s a quick reference before we dive into code examples:

Each section below shows the vulnerable pattern and the fix. /security-audit checks all of these automatically — get it free here.

1. Broken Access Control

What it means: Users can access resources they shouldn’t.

// ❌ VULNERABLE: No permission check
app.get("/admin/users/:id", async (req, res) => {
  const user = await User.findById(req.params.id);
  res.json(user);
});

// ✅ SECURE: Verify admin status
app.get("/admin/users/:id", async (req, res) => {
  if (!req.user.isAdmin) {
    return res.status(403).json({ error: "Forbidden" });
  }
  const user = await User.findById(req.params.id);
  res.json(user);
});

2. Cryptographic Failures

What it means: Sensitive data isn’t encrypted or uses weak encryption.

// ❌ VULNERABLE: Storing passwords in plain text
db.users.insert({ email, password });

// ✅ SECURE: Hash passwords
const hashedPassword = await bcrypt.hash(password, 10);
db.users.insert({ email, password: hashedPassword });

3. Injection

What it means: Untrusted input is executed as code.

// ❌ VULNERABLE: SQL injection
const query = `SELECT * FROM users WHERE email = '${email}'`;

// ✅ SECURE: Parameterized queries
const query = "SELECT * FROM users WHERE email = ?";
db.query(query, [email]);

4. Insecure Design

What it means: The architecture lacks security by design.

Vulnerable pattern:

• User can download any file by guessing URLs
• Password resets allow account takeover
• No rate limiting on login attempts

Secure pattern:

• File access requires ownership check
• Password reset requires email verification
• Rate limiting on sensitive endpoints

5. Security Misconfiguration

What it means: Security features are disabled or misconfigured.

// ❌ VULNERABLE: Debug mode enabled in production
if (process.env.NODE_ENV !== "production") {
  app.use(morgan("combined"));
}

// ✅ SECURE: Never expose debug info
app.use(helmet());

6. Vulnerable and Outdated Components

What it means: You’re using packages with known vulnerabilities.

# Check for known CVEs
npm audit

# Result: 15 vulnerabilities found
# Fix: npm audit fix

7. Authentication Failures

What it means: Weak or broken authentication mechanisms.

// ❌ VULNERABLE: Weak password requirements
if (password.length >= 4) {
  // accept password
}

// ✅ SECURE: Strong password policy
const strongPassword = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{12,}$/;
if (!strongPassword.test(password)) {
  throw new Error("Password too weak");
}

8. Software and Data Integrity Failures

What it means: Updates or data transfers aren’t verified.

// ❌ VULNERABLE: No signature verification on API responses
const data = await fetch(externalAPI).then(r => r.json());

// ✅ SECURE: Verify signature
const signature = response.headers.get("x-signature");
const verified = verifySignature(data, signature, secretKey);
if (!verified) throw new Error("Invalid signature");

9. Logging and Monitoring Failures

What it means: You can’t detect attacks because there’s no logging.

// ❌ VULNERABLE: No audit trail
db.users.update({ id }, { role: "admin" });

// ✅ SECURE: Log all critical actions
logger.info("User role changed", {
  userId: id,
  newRole: "admin",
  changedBy: req.user.id,
  timestamp: new Date()
});

10. Server-Side Request Forgery (SSRF)

What it means: Your server makes requests to untrusted URLs.

// ❌ VULNERABLE: SSRF
app.get("/fetch-url", async (req, res) => {
  const data = await fetch(req.query.url);
  res.json(await data.json());
});

// ✅ SECURE: Whitelist URLs
const allowedDomains = ["trusted1.com", "trusted2.com"];
if (!allowedDomains.some(domain => req.query.url.includes(domain))) {
  return res.status(400).json({ error: "Domain not allowed" });
}

Related: If you’re building autonomous workflows around security, see how to build autonomous agents with Claude Code — you can chain the security audit into your CI/CD pipeline.

Running the Audit in Practice

Phase 1: Code Review (2-3 hours)

Analyze my codebase for:
- All OWASP Top 10 vulnerabilities
- Common security mistakes
- Authentication weaknesses
- Data exposure risks

Create a detailed report with:
- Vulnerability name
- Location (file + line)
- Severity (Critical/High/Medium/Low)
- Explanation
- Proof of concept
- Remediation steps

Claude systematically scans your code and generates findings.

Phase 2: Dependency Audit (30 min)

Check all dependencies in package.json for:
- Known CVEs
- End-of-life packages
- Unnecessary dependencies
- License violations

Generate a list prioritized by severity:
- Critical vulnerabilities = update immediately
- High vulnerabilities = update this release
- Medium vulnerabilities = next release
- Low vulnerabilities = monitor

Phase 3: Configuration Review (1-2 hours)

Review these files for configuration issues:
- .env (sample)
- docker-compose.yml
- nginx.conf
- database setup scripts
- authentication setup
- API security headers

Check for:
- Exposed secrets
- Default credentials
- Unnecessary permissions
- Missing security headers
- Weak TLS configuration

Phase 4: Architecture Assessment (1-2 hours)

Review the architecture for:
- API security (authentication, rate limiting, validation)
- Data flow (where does sensitive data go?)
- Access control (who can do what?)
- Session management
- CSRF protection
- Input validation

Create a security architecture diagram showing:
- External threats
- Internal data flows
- Security controls
- Gaps

Risk Scoring and Prioritization

Not all issues are equal. The audit should score issues by risk:

Risk = Severity × Exploitability × Impact

CRITICAL: Severity 10 × Exploitability 10 × Impact 10
  → Fix immediately, possibly deploy emergency patch
  → Examples: SQL injection, hardcoded passwords, SSRF

HIGH: Severity 10 × Exploitability 7 × Impact 8
  → Fix in this release cycle
  → Examples: Missing rate limiting, weak auth

MEDIUM: Severity 7 × Exploitability 5 × Impact 6
  → Fix in next 1-2 releases
  → Examples: Missing security headers, verbose error messages

LOW: Severity 3 × Exploitability 3 × Impact 3
  → Track and fix when convenient
  → Examples: Outdated package versions, code style issues

Focus on critical issues first. A 2x2 matrix helps:

         High Impact | Low Impact
High      CRITICAL   | MEDIUM
Exploitability

Low       MEDIUM     | LOW
Exploitability

Remediation Workflow

For each finding:

1. Understand: Claude explains the vulnerability in detail
2. Reproduce: Claude provides a proof-of-concept showing the issue
3. Fix: Claude generates patched code
4. Test: You verify the fix works
5. Deploy: You merge and ship
6. Verify: Claude confirms the issue is resolved

Example fix generation:

Finding: SQL injection in /api/search endpoint

Current code:
const query = `SELECT * FROM products WHERE name LIKE '%${searchTerm}%'`;

Generate a fixed version that:
- Uses parameterized queries
- Validates input length
- Escapes special characters
- Maintains the same functionality
- Includes unit tests for the fix

Ongoing Security

An audit is a snapshot. Real security is continuous — and Claude Code workflow automation makes it easy to schedule recurring scans:

1. Set Up Dependency Scanning

# Check for CVEs on every dependency update
npm audit fix --audit-level=moderate

2. Add Pre-Commit Hooks

# Prevent hardcoded credentials from being committed
npx husky add .husky/pre-commit "npx detect-secrets scan"

3. Automated Code Scanning

# GitHub Actions: Run security scan on every PR
name: Security Audit
on: [pull_request]
jobs:
  audit:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - run: npm audit
      - run: npm test

4. Monthly Reviews

Set a calendar reminder to run the security audit monthly. Track:

• New vulnerabilities discovered
• Time to fix critical issues
• Trends in vulnerability types
• Team education opportunities

Tools to Complement Claude Code Audits

• OWASP ZAP: Automated dynamic security scanning
• npm audit: Dependency vulnerability checking
• SonarQube: Code quality and security
• Snyk: Continuous vulnerability monitoring
• Burp Suite Community: Manual penetration testing (advanced)

Use Claude for understanding and comprehensive analysis. Use specialized tools for continuous monitoring.

Reporting Results

Create an audit report for stakeholders:

# Security Audit Report — Q1 2026

## Executive Summary
- Total findings: 47
- Critical: 3 (must fix immediately)
- High: 8 (fix this release)
- Medium: 18 (fix next release)
- Low: 18 (monitor)

## Critical Issues
1. SQL injection in user search
2. Hardcoded AWS credentials
3. Missing CSRF protection

## Compliance Status
- SOC 2: Not ready (3 critical findings must be fixed)
- GDPR: Ready (data deletion implemented)
- PCI DSS: N/A (payment processing delegated to Stripe)

## Recommendations
1. Fix all critical issues before next release
2. Add pre-commit hooks to prevent credential leaks
3. Implement security testing in CI/CD
4. Schedule quarterly audits

Quick-Start Checklist

If you skimmed here, this is the 5-step action plan:

1. Install the security audit skill — free, takes 2 minutes
2. Run /security-audit on your codebase — 30-60 min for most projects
3. Fix critical issues first — SQL injection, hardcoded secrets, broken auth
4. Set up npm audit in CI — catches new CVEs on every pull request
5. Schedule monthly re-audits — use cron jobs with Claude Code to automate it

Already found vulnerabilities? The full Claude Skills 360 suite includes /security-patch, /vulnerability-scanner, and /pentest-checklist — purpose-built skills for fixing what the audit finds. Compare free vs full →

Related Security Skills in Claude Skills 360

Conclusion

Security audits don’t require $15K consultants anymore. Claude Code identifies vulnerabilities, explains impact, and generates fixes — in hours, not weeks.

Your audit will find issues. That’s the point. The value isn’t a perfect score — it’s knowing what’s wrong before attackers do.

Start now: Get the free security audit skill and run it on your codebase today. You’ll have a prioritized vulnerability list before lunch. Ready for the full security toolkit? See all plans →

Frequently Asked Questions

How often should I run AI-powered security audits?

Run a full audit at least quarterly, with automated dependency scanning on every commit. Claude Skills 360 includes security audit skills that can be integrated into your CI/CD pipeline for continuous scanning, plus a monthly review agent that catches new vulnerabilities as they’re disclosed.

Can I try Claude Code skills for free?

Yes — Claude Skills 360 offers a free starter kit with 360 skills across 9 categories. No credit card required. If you want the full suite of 2,350+ skills, 45+ agents, and 12 swarms, you can upgrade for a one-time $39.