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Man-in-the-Middle Attack

What is Man in the Middle Attack?

Imagine a situation: you’re chatting with a friend in a cafe, telling something personal, and suddenly – a stranger quietly moves closer and starts eavesdropping. Moreover – he not only listens, but also inserts his phrases on your behalf, answering for you.

This is approximately how the Man-in-the-Middle Attack, or simply MITM – attack “man in the middle” works. Only instead of a live conversation – digital exchange: you communicate with a bank, messenger or website, and an attacker imperceptibly builds into this channel, reads everything you send, and sometimes even changes the content of messages.

Where Did It All Start? A Bit of History

The first mentions of MITM attacks appeared back in the 1980s – when computers began to communicate with each other on the network. Then it was the “games” of specialists and hackers working at universities. They studied how to intercept traffic between machines to test the security of new protocols.

But the real MITM boom began with the spread of Wi-Fi and mobile networks. Open access points in cafes, shopping malls, and hotels became a gold mine for attacks, as anyone within range could try to intercept other people’s data.

How MITM Works

To keep things simple, here’s a step-by-step explanation:

  1. You connect to the Internet, for example, to Wi-Fi in a coffee shop.
  2. The hacker is also connected to this network.
  3. He launches a special program that “gets in between” you and the site.
  4. You think that you are communicating with the bank, but in reality – with the hacker.
  5. He forwards your request to the bank, and the answer – to you. Everything looks like usual, but … the data has already been stolen.

Main Types of MITM Attacks

MITM is not just one technique, but an entire arsenal. Here are the most common:

  1. Interception in open Wi-Fi networks, this is a classic. You connect to “Free Wi-Fi,” but in reality, you are connecting to an attacker’s fake network. Everything you transmit ends up in someone else’s hands.
  2. ARP Spoofing, it works on a local network. An attacker spoofs the MAC addresses of devices, making your computer think that it is communicating with a router, when it is not.
  3. DNS Spoofing, you enter a website address and end up on a fake page designed to steal logins or credit cards.
  4. HTTPS Stripping, The hacker forces the secure HTTPS connection back to unsecured HTTP, allowing for interception.

What Can Be Stolen in a MITM Attack?

A MITM attack is not just a peeping Tom. It is an opportunity to gain access to the most valuable information:

  • logins and passwords;
  • bank card numbers;
  • the content of correspondence;
  • cookie files (and with them – sessions);
  • documents sent over the network.

What is the Danger of Such an Attack?

The problem with MITM is that it is almost invisible. The user sees a regular page, everything works, nothing “complains”. But in the background:

  • Traffic is recorded;
  • Requests or responses are changed;
  • Viruses are planted;
  • Data is sent to third parties.

Employees of companies working remotely are especially vulnerable if they connect via unsecured networks.

Examples from Real Life

  1. Attacks through fake Wi-Fi at the airport — people connect, open e-mail or online banking, and all information goes to the attacker.
  2. MITM in hotels and coffee shops — in the absence of HTTPS, even messengers can be accessed.
  3. Fake bank pages — copies of popular banking websites are created, and MITM redirects gullible users there.

How MITM Looks Like

  1. You go to your bank’s website: https://moybank.ru
  2. The attack is already working, and you get to https://moybank.ru… only with a fake certificate.
  3. Enter your login and password, click “Log in”.
  4. The hacker gets your data, goes to your account, and you… just wait for the page to load.

Why Does MITM Still Work?

  • People often don’t look at the browser’s lock.
  • Use the same password everywhere.
  • Connect to unfamiliar networks without a VPN.
  • Disable browser or OS updates.
  • Ignore suspicious warnings.

Where MITM is used

When we hear about MITM attacks, we often imagine a hoodie-wearing hacker sitting in a basement. But the reality is more complex. This technique is used not only by malicious actors, but also by legitimate organizations:

  • Corporate monitoring, many large companies implement special proxy servers that intercept all employee internet traffic. Formally, it is to ensure security, content filtering, and leakage prevention. Essentially, it is a “white” version of MITM.
  • Antivirus and security solutions, some antiviruses install their own certificates and create a MITM session to check even HTTPS traffic. This is done for your security… but from a technical standpoint, it is still the same attack.
  • Government control, in some countries, MITM is used by intelligence agencies to monitor citizens, track conversations, and control information. This “digital surveillance” is one of the reasons why more and more people are switching to VPNs and secure messaging apps.

Surprisingly, MITM can also be legal. Here are a few examples:

  • Educational institutions filter student traffic to restrict access to inappropriate websites.
  • Parental controls on home devices may also include MITM filtering.
  • Cybersecurity labs use MITM to test and analyze malware.

The main difference here is transparency and user consent. When you are warned and you agree, it is not an attack. This is protection.

Examples Of Real Incidents

To understand the scale and danger of MITM attacks, it’s worth looking at specific cases. These are not from textbooks or movies, but real-life instances where the middleman in a digital conversation turned out to be someone unexpected.

Lenovo’s Superfish (2015): MITM-inspired advertising

One of the most high-profile corporate scandals, where a Man-in-the-Middle was built into the device from the factory. Lenovo, one of the largest laptop manufacturers, pre-installed a program called Superfish Visual Discovery on some models. Her goal is supposedly to “improve the user experience” by analyzing images and displaying more relevant ads.

In fact, Superfish implemented its own root certificate, which allowed it to substitute for real HTTPS connections. That is, even when accessing secure sites like banks or e-mail, the program could wedge into the connection, read traffic and insert its ads directly into the interface.

The problem was not only in the advertising substitution. Superfish weakened the security of all HTTPS sites, making the user vulnerable to third-party attacks. After the global outrage of the public and the reaction of security specialists, Lenovo was forced to remove the software from new models and release the removal instructions for the old ones.

This was a case when MITM came not from a hacker’s back alley, but through an official channel – from a well-known brand.

MITM in Turkey: The State as an Intermediary (2013)

In 2013, users in Turkey started noticing oddities when accessing Google services: failures, browser warnings about certificates, inability to load Gmail or Google Maps.

Later, it was revealed: government agencies used fake SSL certificates to intercept encrypted traffic to Google domains. This was a classic MITM, but implemented at the national infrastructure level. Instead of directly blocking websites, as is done in other countries, Turkey decided to “become an intermediary.” The goal was not only to observe, but also to replace the content, control access, and monitor user behavior as needed.

Google responded harshly. The company revoked the trust in the certificates used in the Chrome browser and released an urgent security update. This case was not just an incident, but a precedent that clearly demonstrated how MITM can become a tool for digital control at the state level.

DigiNotar (2011): The Hacking That Opened the Door for Everyone

One of the most dangerous cases of MITM attack occurred not through the user’s device, but through the digital certificate system. The Dutch company DigiNotar, which issued SSL certificates, was hacked. The attacker generated hundreds of fake certificates, including a fake certificate for Google.com.

This certificate allowed HTTPS traffic to be intercepted without causing any suspicion in the browser. Someone (presumably a government agency) was using it to monitor users in Iran. In fact, everything looked clean: the address was google.com, the connection was secure, and there was a green padlock. However, the data was being compromised.

The scandal was so widespread that DigiNotar went bankrupt, and browsers and operating systems around the world quickly removed it from their trusted certificate authorities.

This incident showed that the entire SSL system can collapse if just one node fails. This means that MITM doesn’t always require hacking magic – sometimes it’s enough to exploit a trust hole.

MITM in Mobile Networks – When Your Phone Becomes a Postcard

If you think that MITM is only about Wi-Fi and the browser, you will be surprised. Cellular networks can also be an arena for such attacks. Especially vulnerable are old communication standards, such as 2G, where encryption is absent or primitive.

In some countries, special devices – IMSI-keychers or “stingrays” – mimic cell towers. The phone connects to them, thinking that this is an official station, and the attacker begins to intercept calls, SMS and Internet traffic.

The user does not feel a trick. The Internet works. There is a signal. Everything seems to be normal. But on the other side of the screen – no longer an operator, but a curious stranger.

Social Media And MITM – Predator In The Feed

In the era of TikTok and Instagram, MITM attacks and social networks. An attacker can replace content on the fly — insert their own links, change the appearance of the page, or even add themselves to your friend list.

This is especially common in combination with phishing: the user logs in to Facebook using their username and password, but ends up on a fake page generated by the attacker through MITM. Everything looks familiar, but every click goes not to Facebook, but to the attacker’s hands. The deception is complete. The user doesn’t just “click on a link.” He lives in a fake without knowing it.

MITM In Corporate Correspondence – A Business That Leaks

When it comes to corporate e-mails and messengers, MITM becomes especially dangerous. And not only because it is possible to eavesdrop. Much more scary is to fake.

An impressive scenario: an attacker intercepts correspondence between two companies. Say, a contractor and a client. Then, at the right moment, he inserts a letter on behalf of one of the participants with new payment details. Everything looks completely legitimate. The letter is in the same chain. The signature is the same. However, the money has already been misdirected.

Such attacks can cost companies millions. In many cases, it is not the person who fell for the attack that is to blame, but the fact that the MITM attack went unnoticed.

MITM and the Internet of Things — When Even a Light Bulb Gives You Away

When we talk about “smart homes”, most people imagine comfort: voice control, automation, cozy lighting. But if a light bulb, a speaker or a lock is connected to Wi-Fi – they can also become victims of MITM.

Imagine: an attacker intercepts the connection between your smartphone and the “smart home” system. He can spy on commands, reproduce them, or even change them. For example, turn off the alarm or open the door.

The scenario seems like a fantasy, but in reality, such vulnerabilities have already been fixed. MITM in the world of IoT is like breaking a lock, but without a key. Just through the air.

MITM And Browser Extensions – A Trojan Inside The Interface

MITM is not always an external threat. Sometimes, the “man in the middle” is… your own browser. More specifically, an extension that you have installed.

Some plugins (especially free VPNs or proxies) can intercept your traffic and route it through their servers. It sounds convenient: “faster internet,” “saving on data.” But in reality, it’s a pure MITM attack.

The content can be replaced, tracked, and recorded. The user feels that “everything is faster,” but in reality, they have given up some of their privacy in exchange for the illusion of convenience. This is an attack that you have set up yourself.

MITM AND HTTPS, A Shield That Can Be Deceived

Many people believe that if a website uses HTTPS, MITM is impossible. Unfortunately, this is not always the case.

There are methods where an attacker can spoof a certificate to make your browser think that everything is fine. This is especially true if the user has previously accepted a fake root certificate (for example, when installing a suspicious program or antivirus).

In such cases, MITM becomes almost invisible. Everything is encrypted. Everything works. Only the keys are already in the hands of a third party.

MITM And Bank Transactions — A Wallet That Doesn’t Talk To You

When MITM attacks mobile banks or online payments, the consequences can be immediate.

The attacker can change the transfer amount, spoof the recipient, block the confirmation of the transaction, or even monitor each transaction in real-time.

Applications that do not use two-factor authentication or verify digital signatures of data are particularly vulnerable. And if you think you’ve just “transferred a thousand to a friend,” she may have already gone the other way.

MITM And Cloud Services – When Google Drive Stops Being Private

We store documents, spreadsheets, notes, and photos in the cloud. But if your connection is intercepted by a MITM attack, an attacker can see what you’re uploading, downloading, and editing.

Especially if the login is performed without proper certificate verification or through open networks. In this case, even a personal diary in Google Docs can be read by someone other than you.

What is Man in the Middle Attack Conclusion

MITM is not just a technical term from cybersecurity textbooks. It’s a real-life scenario where someone, unbeknownst to you, becomes a third party in your conversation, whether it’s with a bank website, a voice assistant, corporate email, or even your own machine.

This attack can manifest itself in various ways, from infected Wi-Fi in a cafe to fake certificates at the state level. Think of Lenovo’s Superfish, where MITM was hidden in a factory build, or the DigiNotar scandal, where an entire certificate trust system collapsed.

There have also been cases where MITM has been implemented through QR codes, browser extensions, or even through VPN services masquerading as protection.

The key point is that MITM is not always loud or noticeable. However, this is precisely its strength: it operates quietly, discreetly, and individually, but on a large scale. It can be a business model, a government practice, or simply someone’s experiment.

In a world filled with digital intermediaries, the only thing that remains is to be aware of their existence. Because if someone is hiding in the middle, it’s better to guess.