Fixing IDOR

When accessing a record in a DB, we often use a form of identifier (ID) that uniquely identifies a dataset. The DB design and structure rely on these keys, and sometimes they can be easily guessed or enumerated. Adversaries can find these identifiers in your requests to your ASP.NET Core web pages. If not adequately safeguarded with access controls, a malicious user can view, modify, or— at worst—delete these records.

In this recipe, we will discover the IDOR vulnerability in our code and mitigate the problem by using the identity of the authenticated customer.

Getting ready

For the recipes of this chapter, we will need the sample Online Banking app.

Open the command shell and download the sample Online Banking app by cloning the ASP.NET-Core-Secure-Coding-Cookbook repository, as follows:

git clone https://github.com/PacktPublishing/ASP.NET-Core-Secure-Coding-Cookbook.git

Run the sample app to verify that there are no build or compile errors...