Which best describes a man-in-the-middle (MITM) attack?

A man-in-the-middle (MITM) attack is characterized by the attacker secretly intercepting and relaying communication between two parties who believe they are directly communicating with each other. In this type of attack, the attacker can alter or eavesdrop on the communication without either party being aware that their conversation has been compromised. This deceptive positioning allows the attacker to access sensitive information, such as login credentials or personal data, and manipulate the communication for malicious purposes.

This definition aligns precisely with the nature of MITM attacks, emphasizing the covert interception of data which is fundamental to their operation. Understanding this mechanism is crucial for recognizing vulnerabilities in communication protocols and the importance of using encryption to secure data transfers, as it can prevent such attacks from occurring.