// Exploring Authorization-Based Vulnerabilities

In the realm of cybersecurity, proper authorization mechanisms are crucial for protecting sensitive information and system integrity. Authorization determines what authenticated users are allowed to do within a system. This blog post dives into two prevalent types of authorization-based vulnerabilities—Parameter Pollution and Insecure Direct Object Reference—and illustrates how these can be exploited using a hypothetical URL.

Understanding Authorization Vulnerabilities

Before diving into specific vulnerabilities, it’s important to understand the distinction between authentication and authorization. Authentication verifies who the user is, typically through credentials like usernames and passwords. Authorization, however, determines what an authenticated user is allowed to do. Flaws in authorization can lead to significant security risks, allowing users to perform actions beyond their permissions.

1. HTTP Parameter Pollution

HTTP Parameter Pollution (HPP) occurs when a web application processes HTTP requests that include multiple parameters with the same name. This can lead to unexpected behaviour as the application tries to interpret the duplicate parameters.

Example of Exploitation:

Consider a simple URL used in an online store:

https://shop.example.com/?search=cars

An attacker can manipulate this by appending the same parameter with different values:

https://shop.example.com/?search=cars&search=bikes

An attacker could automate the process of sending requests with varying parameters to analyze how the application processes them. Identifying an inconsistency in the response might reveal an HPP vulnerability.

2. Insecure Direct Object References (IDOR)

Insecure Direct Object References occur when an application provides direct access to objects based on user-supplied input. This can allow attackers to bypass authorization and access information they shouldn’t be able to.

Example of Exploitation:

An online store uses direct object references to access customer data:

https://shop.example.com/buy?customerID=1188

By altering the customerID parameter, an attacker could potentially access data belonging to other customers. Using Websploit, an attacker might systematically test different parameter values to explore accessible data without proper authorization.

Preventing Authorization Vulnerabilities

To protect against these vulnerabilities, developers should:

• Use consistent and thorough input validation and sanitization.
• Implement robust authorization checks throughout the application.
• Employ frameworks and libraries that automatically handle duplicate HTTP parameters securely.

Conclusion

Understanding and mitigating authorization-based vulnerabilities are critical for securing web applications. By exploring these vulnerabilities, security professionals can better understand potential risks and refine their security strategies.