What type of attack is likely responsible for multiple failed logins before a successful entry occurs?

A brute-force attack involves systematically attempting every possible combination of passwords until the correct one is found. This method often leads to multiple failed login attempts being recorded before a successful login occurs, as the attacker tries a wide range of potential passwords.

In contrast, a dictionary attack uses a pre-defined list of likely passwords (such as common words or phrases) and operates in a similar way to brute-force but is typically faster because it does not attempt every possible combination. Credential stuffing exploits users' reused passwords across different sites; thus, it aims for success with minimal failed attempts since attackers use passwords obtained from previous data breaches. Password spraying, on the other hand, involves using a smaller set of commonly used passwords across many accounts, resulting in a few failed attempts before potentially hitting a successful login.

Brute-force attacks are characterized by their exhaustive nature and are the type of attack most responsible for the pattern of many failed attempts followed by eventual success.