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Use of a broken or weak cryptographic algorithm

ID: rb/weak-cryptographic-algorithm Kind: problem Security severity: 7.5 Severity: warning Precision: high Tags: - security - external/cwe/cwe-327 Query suites: - ruby-code-scanning.qls - ruby-security-extended.qls - ruby-security-and-quality.qls

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Using broken or weak cryptographic algorithms can leave data vulnerable to being decrypted or forged by an attacker.

Many cryptographic algorithms provided by cryptography libraries are known to be weak, or flawed. Using such an algorithm means that encrypted or hashed data is less secure than it appears to be.

Recommendation

Ensure that you use a strong, modern cryptographic algorithm, such as AES-128 or RSA-2048.

Example

The following code uses the OpenSSL library to encrypt some secret data. When you create a cipher using OpenSSL you must specify the encryption algorithm to use. The first example uses DES, which is an older algorithm that is now considered weak. The second example uses AES, which is a stronger modern algorithm.

require 'openssl' class Encryptor  attr_accessor :secret_key  def encrypt_message_weak(message)  cipher = OpenSSL::Cipher.new('des') # BAD: weak encryption  cipher.encrypt  cipher.key = secret_key  cipher.update(message)  cipher.final  end  def encrypt_message_strong(message)  cipher = OpenSSL::Cipher::AES128.new # GOOD: strong encryption  cipher.encrypt  cipher.key = secret_key  cipher.update(message)  cipher.final  end end

References