The 30-Minute Security Audit: Onboarding a New Codebase

Source: Dev.to

You just inherited a codebase. Maybe it’s an acquisition, a departing senior engineer, or you’re the new CTO and nobody can explain why there’s a utils/legacy_auth.js file with 3,000 lines.

You need to know: How bad is it?

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The Old Way: Pain

Traditionally, security audits take weeks. You bring in consultants, they run tools, they produce a 200‑page PDF, you file it and forget.

But you don’t have weeks. You need a pulse check today.

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The 30‑Minute Approach

Here’s how to assess a new codebase in under 30 minutes.

Step 1: Install (2 minutes)

npm install --save-dev eslint-plugin-secure-coding
npm install --save-dev eslint-plugin-pg
npm install --save-dev eslint-plugin-crypto

Step 2: Configure for Maximum Detection (3 minutes)

// eslint.config.js
import secureCoding from 'eslint-plugin-secure-coding';
import pg from 'eslint-plugin-pg';
import crypto from 'eslint-plugin-crypto';

export default [
  secureCoding.configs.strict,
  pg.configs.recommended,
  crypto.configs.recommended,
];

The strict preset enables all 75 secure‑coding rules as errors—perfect for an initial scan.

Step 3: Run the Audit (5 minutes)

npx eslint . --format=json > security-audit.json

You’ll see violations like:

src/auth/login.ts
  18:5   error  🔒 CWE-798 OWASP:A07-Auth-Failures CVSS:7.5 | Hardcoded API key detected | HIGH
                   Fix: Move to environment variable: process.env.STRIPE_API_KEY

src/utils/crypto.ts
  42:10  error  🔒 CWE-327 OWASP:A02-Crypto-Failures CVSS:7.5 | Weak algorithm (MD5) | HIGH
                   Fix: Use a strong algorithm: crypto.createHash('sha256')

Step 4: Analyze and Prioritize (20 minutes)

cat security-audit.json | jq '.[] | .messages[] | .ruleId' | sort | uniq -c | sort -rn

You now have a prioritized list:

• 15 hits on pg/no-unsafe-query = 🔴 Critical
• 8 hits on secure-coding/no-hardcoded-credentials = 🔴 Critical
• 3 hits on crypto/no-weak-hash = 🟡 Medium

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What This Tells You

In 30 minutes you know:

• The attack surface – Which OWASP categories are most exposed.
• The hotspots – Which files have the most issues.
• The culture – Did the previous team care about security?

This isn’t a replacement for a full penetration test, but it’s a data‑driven starting point for your first board meeting.

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Bonus: Let AI Fix It

The structured error messages are designed for AI coding assistants. Once you’ve identified your top issues, let the AI suggest fixes—most can be resolved with a single keystroke.

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What’s Next?

• Enforce it – Add the plugins to your CI pipeline to block new issues.
• Automate compliance – Use the built‑in SOC2/PCI tags for audit evidence.
• Track progress – Re‑run weekly to measure remediation velocity.

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Quick Install

• 📦 eslint-plugin-secure-coding – 75 security rules
• 📦 eslint-plugin-pg – PostgreSQL security
• 📦 eslint-plugin-crypto – Cryptography security