A man-in-the-middle (MITM) attack is a cyber attack where an attacker intercepts communications between two parties without their knowledge by positioning themselves in the middle. This allows the attacker to eavesdrop on or manipulate transmitted data, potentially leading to unauthorized access and data theft. In 2011, the ComodoHacker successfully tricked a registration authority into issuing fraudulent SSL certificates for popular websites, enabling the attacker to intercept user logins and other private information. To protect against MITM attacks, it is important to use encryption, verify certificates, keep devices updated, enable two-factor authentication, and be cautious of phishing attempts.