# Use of a Broken or Risky Cryptographic Algorithm (CWE-327)

The product uses a broken or risky cryptographic algorithm or protocol.

**Stack:** Python

- Prevalence: High Frequently exploited
- Impact: High 3 high-severity rules
- Prevention: Documented 4 fix examples

**OWASP:** Cryptographic Failures (A02:2021-Cryptographic Failures) - #2

## Description

Cryptographic algorithms are the backbone of modern information security. Using algorithms that have known weaknesses, such as MD5 or DES, can make it trivial for attackers to defeat the protection.

## Prevention

Prevention strategies for Broken Cryptographic Algorithm based on 1 Shoulder detection rules.

### Python

Replace MD5/SHA-1/DES/RC4 with SHA-256/SHA-3 for hashing and AES-GCM for encryption

## Warning Signs

- [MEDIUM] use of weak or deprecated cryptographic algorithms like MD5, SHA-1,
DES, or RC4

## Consequences

- Read Application Data
- Bypass Protection Mechanism

## Mitigations

- Use AES-256 for symmetric encryption
- Use RSA-2048+ or ECDSA for asymmetric encryption
- Use SHA-256 or SHA-3 for hashing

## Detection

- Total rules: 4
- Languages: go, javascript, typescript, python

## Rules by Language

### Python (1 rules)

- **Weak Cryptographic Algorithm** [MEDIUM]: Detects use of weak or deprecated cryptographic algorithms like MD5, SHA-1,
DES, or RC4. Use modern algorithms like SHA-256, SHA-3, AES, or ChaCha20.
  - Remediation: Use SHA-256/SHA-3 for hashing and AES for encryption.

```python
import hashlib
from Crypto.Cipher import AES
from Crypto.Random import get_random_bytes

# Secure hashing
hash_value = hashlib.sha256(data).hexdigest()

# Secure encryption
key = get_random_bytes(32)  # AES-256
cipher = AES.new(key, AES.MODE_GCM)
ciphertext, tag = cipher.encrypt_and_digest(data)
```

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