Understanding injection-based attacks
Injection-based attacks allow threat actors and penetration testers to inject customized code into an input field within a form on a web application. The web application will process the input and provide a response, as it is designed to operate in a client-server model and a request-response model too. However, if a user sends malformed code to a login form on a web application, the user may be able to retrieve sensitive information from the web application and the database server, and even perform operations on the operating system of the hosting web server.
Without proper validation and sanitization of users' input, threat actors are able to determine whether a web application has security vulnerabilities, manipulate the data stored within the backend database server, and even perform command injections on the host operating system.
The following diagram shows a visual representation of a web server deployment: