Patched code sample

import hashlib
import secrets
import base64
from cryptography.fernet import Fernet

def encrypt_data(data, password):
    # SECURE: Use strong encryption with proper key derivation
    
    if not isinstance(data, str) or not isinstance(password, str):
        raise ValueError("Data and password must be strings")
    
    # Generate a random salt
    salt = secrets.token_bytes(16)
    
    # Derive a strong key using PBKDF2
    key = hashlib.pbkdf2_hmac('sha256', password.encode(), salt, 100000)
    
    # Use Fernet for authenticated encryption
    fernet_key = base64.urlsafe_b64encode(key)
    fernet = Fernet(fernet_key)
    
    # Encrypt the data
    encrypted_data = fernet.encrypt(data.encode())
    
    # Return salt + encrypted data for storage
    return base64.b64encode(salt + encrypted_data).decode()

def decrypt_data(encrypted_data, password):
    # SECURE: Corresponding decryption function
    
    try:
        # Decode the stored data
        combined_data = base64.b64decode(encrypted_data.encode())
        
        # Extract salt and encrypted data
        salt = combined_data[:16]
        encrypted = combined_data[16:]
        
        # Derive the same key
        key = hashlib.pbkdf2_hmac('sha256', password.encode(), salt, 100000)
        fernet_key = base64.urlsafe_b64encode(key)
        fernet = Fernet(fernet_key)
        
        # Decrypt and return
        decrypted_data = fernet.decrypt(encrypted)
        return decrypted_data.decode()
        
    except Exception as e:
        raise ValueError(f"Decryption failed: {e}")

# Example of secure usage:
# strong_encrypted = encrypt_data("secret", "password")  # Strong AES encryption
# decrypted = decrypt_data(strong_encrypted, "password")  # Secure decryption