Parameter pollution is a security vulnerability that can occur in web applications when user supplied data, such as query parameters, form inputs, or cookies, are not properly validated or sanitized before being used to make critical decisions or perform actions on the server side.
For example, in a URL like https://example.com/page?name=John&age=30 , "name" and "age" are parameters with the values "John" and "30," respectively.
Tempering the values of the parameters “name” and “age” can lead to various types of attacks, such as injection attacks or privilege escalation.
The most common form of parameter pollution occurs when an attacker manipulates the input parameters to modify the application's behavior in unintended ways.
For example, in a URL like https://example.com/page?name=John&age=30 where “name” and “age” are parameters.If an attacker replace the value “John” with “Robert” and can get logged-in with the Robert account he can easily modify data and execute malicious actions.
The process of altering the value of “name” parameters from “John” to “Robert” is known as parameter pollution.
To mitigate parameter pollution vulnerability:
Ensure that all input data, whether from the user or external sources, must be validated and sanitized before being used in any critical operations.
Ensure that sensitive operations, such as authentication and authorization, are not solely relying on user supplied data but also incorporate strong access controls and validation checks.
When interacting with databases, utilize prepared statements and parameterized queries to prevent SQL injection attacks.