Broken Access Control: Auditing Insecure Object References (IDOR)

Broken Access Control is a critical web vulnerability. Insecure Direct Object References (IDOR) occur when an application accesses records using direct database keys without verifying user authorization.

1. How IDOR Works

Consider an invoice download URL:

https://target.com/download?invoice_id=1005

If a user changes the parameter `invoice_id` to `1004` and the server displays the record without validating ownership, the user has successfully bypassed authorization boundaries.

2. Remediation

Always implement server-side access control checks. Before returning data, verify that the logged-in session has permissions to view the requested record ID.