An attacker has set up a system that tricks the user's computer into thinking the attacker is the server and tricks the server into thinking the attacker is the user's computer. What is the name of this type of attack?

In this scenario, the type of attack described is known as a Man-in-the-Middle (MITM) attack. This occurs when an attacker intercepts and potentially alters the communication between two parties, in this case, the user and the server. The attacker effectively places themselves between the two endpoints, enabling them to manipulate the data being exchanged or to eavesdrop on the communication without either party being aware that a third party is involved.

The key aspect of a MITM attack is the deception involved, as the attacker masquerades as each party to the other. This allows the attacker to steal credentials, redirect users to malicious sites, and gain unauthorized access to sensitive information. The fundamental mechanics of the attack hinge on establishing trust between the entities, which the attacker undermines.

In contrast, other types of attacks listed, such as Denial of Service (DoS), primarily aim to disrupt service availability rather than intercept data. Phishing attacks are focused on tricking users into revealing personal information, and SQL injection involves manipulating a database through insecure code, rather than intercepting traffic. Each of these has a distinct mechanism and objective, which differentiates them from the deceptive nature of a MITM attack.