Password hashes use bcrypt or argon2 (not raw crypto)

Storing crypto.createHash('sha256').update(password).digest('hex') as a password hash is not password hashing — it's a fingerprint. SHA-256 runs at ~3 billion hashes per second on a gaming GPU, making a leaked database crackable in hours for common passwords. CWE-916 (Use of Password Hash With Insufficient Computational Effort) and OWASP A02 describe the requirement: password KDFs (bcrypt, argon2, scrypt) are deliberately slow — 250ms per attempt — which makes brute-force impractical. An AI-generated auth module that uses crypto.createHash instead of bcrypt.hash is the most common credential-storage mistake in vibe-coded projects.

Replace any crypto.createHash call on passwords with bcrypt.hash() or argon2.hash(). Both are purposefully slow and include a random salt automatically.

// Bad: fast, saltless, GPU-friendly
const hash = crypto.createHash('sha256').update(password).digest('hex')

// Good: bcrypt with cost factor 12 (~250ms on modern hardware)
import bcrypt from 'bcrypt'
const hash = await bcrypt.hash(password, 12)

// Verification
const valid = await bcrypt.compare(candidatePassword, storedHash)

// Or argon2 (preferred for new projects)
import argon2 from 'argon2'
const hash = await argon2.hash(password)
const valid = await argon2.verify(storedHash, candidatePassword)

If you have existing SHA-256 hashes in production, plan a migration: on next successful login, re-hash with bcrypt and store the new hash.