Need

Implementation of robust security controls for fingerprint identification

Context

• Usage of Ruby for building dynamic and object-oriented applications
• Usage of Ruby on Rails for building web applications

Description

Non compliant code

        class UsersController < ApplicationController
  def login
    user = User.find_by_username(params[:username])
    if user
      session[:user_id] = user.id
      redirect_to root_url, notice: "Logged in!"
    else
      flash.now.alert = "Username is invalid"
      render "new"
    end
  end
end
        
        

In the above Ruby on Rails code, the login method in the UsersController is used to authenticate a user based on their username only. The find_by_username method is used to find the user in the database, and if a match is found, the user is logged in and a session is created for the user with their user_id.

This code is vulnerable because it does not require any form of password or fingerprint authentication. An attacker can easily bypass security controls just by knowing the username of a user. This can lead to unauthorized access to the application, potentially leading to data leakage, data manipulation, and other security breaches.

Steps

• Implement a secure authentication mechanism that includes fingerprint verification.
• Use a secure and reliable fingerprint recognition library or API.
• Ensure that the fingerprint verification process is properly integrated into the login flow.
• Validate the fingerprint data received from the client to prevent tampering or spoofing.
• Implement appropriate error handling and logging for any fingerprint verification failures.
• Regularly update and patch the fingerprint recognition library or API to address any security vulnerabilities.
• Conduct regular security assessments and penetration testing to identify and address any potential weaknesses in the fingerprint verification system.

Compliant code

        class UsersController < ApplicationController
  def login
    user = User.find_by_username(params[:username])
    if user && user.authenticate_fingerprint(params[:fingerprint])
      session[:user_id] = user.id
      redirect_to root_url, notice: "Logged in!"
    else
      flash.now.alert = "Username or fingerprint is invalid"
      render "new"
    end
  end
end

class User < ApplicationRecord
  def authenticate_fingerprint(fingerprint)
    # Implement your fingerprint authentication logic here
    # This is just a placeholder
    self.fingerprint == fingerprint
  end
end
        
        

The updated code now includes a fingerprint authentication mechanism in the login process. When a user attempts to log in, the system will not only check the username but also verify the user's fingerprint.

In the login method of the UsersController class, we added a call to user.authenticate_fingerprint(params[:fingerprint]). This method is expected to return true if the provided fingerprint matches the one stored in the database for the user, and false otherwise.

The authenticate_fingerprint method should be implemented in the User model. The placeholder implementation provided here simply checks if the provided fingerprint matches the one stored in the fingerprint attribute of the User instance. In a real-world application, this method should use a secure and reliable fingerprint recognition library or API to verify the fingerprint.

If the username is found and the fingerprint is verified, the user is logged in and redirected to the root URL. If either the username is not found or the fingerprint is not verified, an error message is displayed and the login form is re-rendered.

This solution helps to prevent security control bypass by ensuring that the user is who they claim to be, based on their unique fingerprint. It also helps to prevent unauthorized access to the system.

References

• 436. Security controls bypass or absence - Fingerprint