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Insecure encryption algorithm

Need​

Secure encryption algorithm implementation

Context​

  • Usage of Scala for building scalable and high-performance applications
  • Usage of javax.crypto.Cipher for cryptographic operations
  • Usage of javax.crypto.spec.SecretKeySpec for creating a secret key specification in Java cryptography

Description​

Non compliant code​

import javax.crypto.Cipher
import javax.crypto.spec.SecretKeySpec

val data = "SensitiveData"
val key = "InsecureKey12"

val cipher = Cipher.getInstance("DES")
val secretKey = new SecretKeySpec(key.getBytes, "DES")

cipher.init(Cipher.ENCRYPT_MODE, secretKey)
val encryptedData = cipher.doFinal(data.getBytes)

In the code above, an insecure encryption algorithm, DES (Data Encryption Standard), is used to encrypt sensitive data. DES is considered insecure because it uses a relatively small key size (56 bits), which can be brute-forced with modern computational power.

The encryption process in the code is as follows:

  1. Cipher.getInstance("DES") is used to get an instance of the DES cipher.
  2. new SecretKeySpec(key.getBytes, "DES") is used to generate a key from a string. This key is used for both encryption and decryption. The key size is also small and can be easily guessed or brute-forced.
  3. cipher.init(Cipher.ENCRYPT_MODE, secretKey) is used to initialize the cipher in encryption mode with the secret key.
  4. cipher.doFinal(data.getBytes) is used to encrypt the sensitive data.

Using this insecure encryption method can lead to sensitive data being decrypted by attackers, leading to a potential data breach.

Steps​

  • Replace the insecure encryption algorithm with a secure one, such as AES.
  • Generate a strong and random encryption key.
  • Use a secure key management system to store and retrieve the encryption key.
  • Ensure that the encryption key is not hard-coded in the code.
  • Implement proper key rotation and key revocation mechanisms.
  • Follow best practices for encryption, such as using authenticated encryption modes and proper padding schemes.
  • Regularly update the encryption library and dependencies to stay up-to-date with security patches.

Compliant code​

import javax.crypto.Cipher
import javax.crypto.spec.SecretKeySpec
import javax.crypto.KeyGenerator
import java.security.SecureRandom

val data = "SensitiveData"

// Generate a strong and random encryption key
val keyGenerator = KeyGenerator.getInstance("AES")
keyGenerator.init(256, new SecureRandom())
val secretKey = keyGenerator.generateKey()

val cipher = Cipher.getInstance("AES")
cipher.init(Cipher.ENCRYPT_MODE, secretKey)
val encryptedData = cipher.doFinal(data.getBytes)

The original code was using the DES encryption algorithm, which is considered insecure due to its small key size. The new code uses the AES encryption algorithm, which is currently the industry standard for encryption and is considered secure.

The original code was also using a hard-coded encryption key, which is a bad practice because it makes the encryption easy to break if the key is discovered. The new code generates a strong and random encryption key using the KeyGenerator class. This key is 256 bits long, which is the maximum length allowed for AES and provides a high level of security.

The SecureRandom class is used to initialize the key generator. This class provides a cryptographically strong random number generator (RNG). Using a strong RNG is important to ensure that the encryption key is truly random and cannot be guessed.

The encryption key is then used to initialize the Cipher object in encryption mode. The data is encrypted using the doFinal method of the Cipher object.

Please note that this code does not include a key management system. In a real-world application, the encryption key should be securely stored and retrieved using a key management system. The key should not be hard-coded in the code, as was done in the original code.

Also, this code does not implement key rotation and key revocation mechanisms. These are important features to have in a secure system. Key rotation refers to the practice of regularly changing the encryption key. Key revocation refers to the ability to invalidate an encryption key if it is compromised.

Finally, it's important to regularly update the encryption library and its dependencies to stay up-to-date with security patches. This can help protect against known vulnerabilities in the encryption algorithm or library.

References​

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