This type of injection attack does not show any error message. It is difficult to exploit as it returns information when the application is given SQL payloads that elicit a true or false response from

Union SQL injection relies on using the UNION operator to combine the results of an injected query with the legitimate query, directly returning data to the attacker, which contradicts the scenario's lack of direct output.

Error-based SQL injection relies on the database displaying specific error messages that contain sensitive information about the database structure or data, directly contradicting the statement that 'does not show any error message'.

Time-based SQL injection is a type of blind SQL injection that infers information by observing delays in the server's response time, which is different from the true/false response mechanism described in the question, although it is also a blind technique.

Blind SQL injection is an attack where the attacker infers information by observing the application's response to injected SQL queries, without the database directly outputting data or error messages. The scenario perfectly describes boolean-based blind SQL injection, a specific technique where true/false conditions elicited by SQL payloads are used to extract information iteratively.