Need

Protection of sensitive corporate information from unauthorized access

Context

• Usage of Python 3.6+ for developing Python applications
• Usage of Django for building web applications in Python

Description

Non compliant code

        from django.views import View
from django.http import HttpResponse
from .models import Employee

class EmployeeView(View):
    def get(self, request):
        employees = Employee.objects.all()
        response = ''
        for employee in employees:
            response += f'Name: {employee.name}, Role: {employee.role}, Contact: {employee.contact}
'
        return HttpResponse(response)
        
        

In the code above, we have a Django view named EmployeeView. This view handles GET requests and retrieves all employees from the database, including their names, roles, and contact information. The problem here is that there is no access control implemented, meaning that anyone who can make a GET request to this endpoint can retrieve all this information.

This is a serious security vulnerability as it can lead to a business information leak. Sensitive data such as employee roles and contact information can be accessed by anyone, including potential attackers. This information can be used for social engineering attacks, identity theft, and other malicious activities.

The EmployeeView should be modified to ensure that only authorized users can access the employee information. This can be achieved by implementing proper authentication and authorization controls. For example, only users with a specific role (e.g., HR manager) should be able to access this information.

Steps

• Implement authentication and authorization checks to ensure only authorized users can access the employee data.
• Limit the amount of information that is displayed. Sensitive information such as contact details should not be displayed unless necessary.
• Use Django's built-in permissions and groups to manage who has access to what data.
• Consider using Django's built-in User model for employee data, which comes with many security features out of the box.
• Encrypt sensitive data in the database and decrypt it when it needs to be displayed.
• Log all access to sensitive data to be able to track any potential data breaches.

Compliant code

        from django.contrib.auth.decorators import login_required, permission_required
from django.views import View
from django.http import HttpResponse
from .models import Employee

class EmployeeView(View):
    @login_required
    @permission_required('app.view_employee', raise_exception=True)
    def get(self, request):
        employees = Employee.objects.all()
        response = ''
        for employee in employees:
            response += f'Name: {employee.name}, Role: {employee.role}
'
        return HttpResponse(response)
        
        

The updated code now includes Django's built-in decorators @login_required and @permission_required to ensure that only authenticated and authorized users can access the employee data.

The @login_required decorator ensures that the user is authenticated before they can access the view. If a user who is not authenticated tries to access the view, they will be redirected to the login page.

The @permission_required decorator checks if the logged-in user has the specific permission to view employee data. In this case, the permission is 'app.view_employee'. If the user does not have this permission, an exception will be raised and the user will be redirected to an error page. You can replace 'app.view_employee' with the actual permission in your application.

In the get method, we are now only displaying the employee's name and role. The contact information is no longer included in the response to protect the privacy of the employees.

This way, we are limiting the amount of information that is displayed and ensuring that only authorized users can access this information, thereby fixing the business information leak vulnerability.

References

• 336. Business information leak - Corporate information