# Use of Weak Cryptographic Algorithm

- ID: javascript-weak-crypto-algorithm
- Severity: HIGH
- CWE: Broken Cryptographic Algorithm (CWE-327)
- Languages: JavaScript, TypeScript
- Frameworks: express, fastify, nextjs

## Description

Detects use of weak or broken cryptographic algorithms for hashing passwords
or sensitive data.

**Weak algorithms detected:**
- **MD5**: Cryptographically broken, vulnerable to collision attacks
- **SHA1**: Deprecated, vulnerable to collision attacks
- **DES/3DES**: Weak block cipher with small key size
- **RC4**: Stream cipher with known vulnerabilities

**Impact:**
- Password hashes can be cracked using rainbow tables or brute force
- Data encrypted with weak algorithms can be decrypted by attackers
- Integrity of hashed data cannot be guaranteed

**For password hashing**, use:
- bcrypt (recommended)
- scrypt
- argon2
- PBKDF2 with strong parameters

**For general hashing**, use:
- SHA-256 or SHA-512 (for non-password data)
- SHA-3 for future-proofing

**For encryption**, use:
- AES-256-GCM
- ChaCha20-Poly1305

## Remediation

Use bcrypt/argon2 for passwords, SHA-256+ for hashing, and AES-256-GCM for encryption.

```javascript
const bcrypt = require('bcrypt');
const hash = await bcrypt.hash(password, 12);
```

Learn more: https://shoulder.dev/learn/javascript/cwe-327/weak-crypto-algorithm

## Documentation

[object Object]

## Related Rules

- **Use of Weak Cryptographic Algorithm** [HIGH]: 
- **JWT Algorithm Confusion Attack** [HIGH]: 
- **Weak Cryptographic Algorithm** [MEDIUM]: