Need

Implementation of secure encryption algorithms

Context

• Usage of Ruby for developing dynamic and object-oriented applications
• Usage of digest for generating and verifying message digests

Description

Non compliant code

        require 'digest/md5'

def encrypt_data(data)
  Digest::MD5.hexdigest(data)
end
        
        

The above code represents the usage of an insecure encryption algorithm, MD5, in a Ruby on Rails application. In the function encrypt_data, the input data is encrypted using the Digest::MD5.hexdigest method.

MD5 is a widely used cryptographic hash function that produces a 128-bit (16-byte) hash value. It is commonly used to verify data integrity. However, MD5 is not a secure way to store sensitive data like passwords because it's vulnerable to hash collisions. This means that different inputs can produce the same hash output, making it easier for an attacker to guess the input using a rainbow table or other methods.

In this context, if an attacker is able to access the hashed data, they might be able to reverse-engineer the original input. This is a serious security risk if the data being hashed includes sensitive information such as user passwords.

Therefore, it is recommended to use a more secure encryption algorithm, such as bcrypt or scrypt, which are designed to be resistant to brute-force search attacks.

Steps

• Step 1: Replace the insecure encryption algorithm with a secure one.
• Step 2: Use a strong cryptographic hash function, such as SHA-256 or bcrypt, instead of MD5.
• Step 3: Update the code to use the new encryption algorithm.
• Step 4: Ensure that the encryption algorithm is properly implemented and configured.
• Step 5: Test the updated code thoroughly to ensure it functions correctly and securely.

Compliant code

        require 'bcrypt'

def encrypt_data(data)
  BCrypt::Password.create(data)
end
        
        

The original code was using the MD5 algorithm for encryption, which is considered insecure due to its vulnerability to collision attacks. This means that two different inputs can produce the same hash output, making it easier for an attacker to reverse-engineer the original data.

The updated code uses the bcrypt algorithm, which is currently considered a secure method for password hashing. Bcrypt is designed to be slow and computationally intensive, which makes it more resistant to brute force attacks. It also automatically handles the creation of a random salt, which is used to protect against rainbow table attacks.

The BCrypt::Password.create(data) method will hash the data input and return a string that includes the salt and the hash. When you need to verify a password, you can use BCrypt::Password.new(hashed_password).is_password?(unhashed_password).

Please note that while bcrypt is a good choice for password hashing, it may not be the best choice for all types of data encryption. Always choose the encryption algorithm that is most appropriate for your specific use case.

After updating the encryption algorithm, make sure to thoroughly test the updated code to ensure it functions correctly and securely.

References

• 052. Insecure encryption algorithm