Definition
An Insecure Direct Object Reference IDOR is a type of security vulnerability where an application exposes a reference to an internal implementation object, such as a file, directory, or database record, without proper authorization checks. This allows an attacker to manipulate these references, often through parameters in URLs or form fields, to gain unauthorized access to data or perform actions they should not be able to. Understanding IDOR is crucial for secure software development and system administration, as it can lead to significant data breaches and unauthorized system modifications. For example, changing a user ID in a URL like `example.com/account?id=123` to `example.com/account?id=456` might allow access to another user's account if validation is missing. Unlike broken access control, which is a broader category, IDOR specifically targets the direct referencing of objects. This vulnerability is frequently covered in cybersecurity certifications like CompTIA Security+ and CISSP.