What is a man-in-the-middle attack (#MITM)?

In the world of cryptocurrencies or computer security, a man-in-the-middle attack (#MITM) is basically when an intruder places themselves between two people who are communicating. It seems terrifying how these attackers can spy, intercept, or even modify the information traveling between both parties without their knowledge.

The victims believe they are speaking directly to each other, but in reality, there is someone else listening to everything. For it to work, the perpetrator must capture all the messages and insert new ones. It sounds complicated, but sadly it is quite simple in many cases; an unencrypted WiFi is fertile ground for these attacks.

#MITM attacks are used to steal credentials, private keys, or sabotage communications. Although encryption offers some protection, more skilled attackers redirect traffic to phishing sites that appear legitimate or simply log the information before sending it to its real destination, making detection nearly impossible.

These attacks aim to circumvent mutual authentication and only work when the intruder convincingly impersonates both ends of the communication. That is why many cryptographic protocols use endpoint authentication, such as TLS with mutually trusted certificates.

One should not confuse a man-in-the-middle attack with a meet-in-the-middle attack; they are different things even though they sound similar.

Notice: includes third-party opinions. It is not financial advice. It may contain sponsored content.