A Bug Bounty Hunter’s Guide to IDOR Vulnerabilities

Introduction

IDORs, or “Insecure Direct Object References”, are a type of security vulnerability that can occur in web applications. IDORs occur when an application exposes a direct object reference, such as a file or database record, without proper authorization checks in place. This can allow an attacker to access or modify sensitive data that they should not have access to.

Types of IDORS

Common IDOR vulnerabilities include:

— Lack of proper authorization checks: This is the most common cause of IDORs. If an application does not properly check if a user is authorized to access a certain object, then an attacker may be able to bypass these checks and access the data.

— Insufficient entropy: If an application uses predictable or easily guessed direct object references, then an attacker may be able to guess or brute force their way to the data.

— Incorrect permissions: If an application sets incorrect permissions on direct object references, then unauthorized users may be able to access the data.

Location and Exploitation

There are two main ways to find IDORs: manually and automatically. Manual testing involves manually examining the…