Skip to main content

Insecure functionality - Masking

Need

Secure data masking

Context

  • Usage of Python 3 for writing and executing Python code
  • Usage of Django for building web applications in Python

Description

Non compliant code

from django.http import JsonResponse

def user_info(request):
user = request.user
response_data = {
'username': user.username,
'email': user.email,
'password': user.password
}
return JsonResponse(response_data)

This piece of Django code represents a backend route that returns a JSON response with user information. The function user_info(request) is called when a request is made to the server. It retrieves the user object from the request and then prepares a dictionary response_data with user's username, email, and password.

The major vulnerability in this code is that the password of the user is being sent in the response. This is a clear example of insecure functionality - masking. The password is a sensitive piece of information and should never be sent in a response, even if it's hashed.

It's also important to note that, depending on Django configuration, this password may not be hashed and could be in plain text, which is an even more significant security risk.

An attacker who intercepts this response would have access to the user's password, which could be used for unauthorized access to the user's account, or even worse, if the user uses the same password on other platforms, the attacker could gain access to those as well. This is a serious security vulnerability and needs to be fixed.

Steps

  • Remove the 'password' field from the response data. Never expose sensitive data like passwords in any API response.
  • Implement data masking for the 'email' field. You can mask the email by showing only a few characters and replacing the rest with asterisks or any other symbol.
  • Use Django’s built-in authentication system which stores passwords securely by default.
  • Consider using HTTPS for data transmission to ensure data is encrypted during transit.

Compliant code

from django.http import JsonResponse

def user_info(request):
user = request.user
masked_email = user.email[:3] + '****' + user.email.split('@')[-1]
response_data = {
'username': user.username,
'email': masked_email,
}
return JsonResponse(response_data)

The updated code removes the 'password' field from the response data. This is a crucial step as exposing sensitive data like passwords in any API response can lead to serious security breaches.

The 'email' field is masked by showing only the first three characters and the domain name, replacing the rest with asterisks. This way, we can still provide some information without revealing the entire email address. The masking is done using Python's string slicing and concatenation features.

Remember, it's also recommended to use Django’s built-in authentication system which stores passwords securely by default. This means that even if someone gains access to your database, they won't be able to retrieve the original passwords.

Finally, consider using HTTPS for data transmission to ensure data is encrypted during transit. This adds an extra layer of security by making it harder for attackers to intercept and read the data.

References