How to Prevent a Man-in-the-Middle Attack
The modern tech ecosystem is a vast array of devices, networks, and connections. With so much information flowing through so many channels, malicious actors intent on intercepting communications have numerous vulnerabilities to exploit. Man-in-the-middle attack prevention requires an approach that accounts for and comprehensively protects each of these vulnerabilities.
If you want to learn more about how to neutralize this threat, then read on. This article is your guide to the current best practices for man-in-the-middle attack prevention.
For more on ensuring your network security, check out Network Threats: How to Detect and Prevent the 5 Most Common Attacks.
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What Is a Man-in-the-Middle Attack?
Man-in-the-middle attacks (MITM) are a type of cyberattack where a bad actor exploits the information flowing between two parties. This exploitation could take many forms, including eavesdropping, sending fake messages, accessing private accounts, or pushing data to another malicious party. While MITM attacks are common, they are also severe. They enable cybercriminals to access the most valuable asset organizations have: their information.
How Do Man-in-the-Middle Attacks Work?
Here is a simple example that illustrates how man-in-the-middle attacks work: Imagine there are two parties, Alice and Bob, that are having a conversation across the internet. Alice and Bob want to keep this conversation private because they are talking about sensitive information.
Another party, Greg, wants to know what Alice and Bob are talking about, but he doesn’t want them to know he is listening in. Because the conversation is not in person, Greg could potentially put himself between Alice and Bob, pose as Bob to Alice and Alice to Bob, learn what each has to say, and pass the information — or change it — on to the other party without either of them knowing.
Now that we have reviewed the fundamentals let us look at specific types of man-in-the-middle attacks.
What Are the Types of Man-in-the-Middle Attacks?
While the concept of man-in-the-middle attacks is simple, the number of techniques used to carry them out is almost endless. Below are some of the most common forms of MITM attacks.
Router spoofing: One of the most popular man-in-the-middle attacks, router spoofing, is when a malicious actor creates a fake wifi network that resembles real networks in the area to trick users into connecting. Once they do, the attacker has access to the data flowing from the user’s device.
Email phishing: This is where a malicious actor attempts to access sensitive information using fake emails. Phishing scams often use emails that mimic official sources — like a company executive or a bank representative — to request login credentials, account information, and other details from unsuspecting users.
HTTPS spoofing: In this attack, malicious actors use a fake version of an HTTPS site to trick users into giving them their information after redirecting them there. It is a problematic ruse to spot, as the site URL looks almost identical to the actual site: Attackers often use a slightly different alphabet or clever letter swaps to pull off the counterfeit.
ARP cache poisoning: This is where an attacker accesses a system that sits between a user's endpoint and a local network. Once a user connects, the attacker has access to all the information moving between the user's device and the network.
IP spoofing: Counterfeiting is the name of the game for MiTM attacks, and this technique is no different, which uses a fake IP address to lure users into disclosing essential data.
Inside man: This is where an attack is assisted or orchestrated by a team member at the target organization. With insider knowledge of the operations, everything about executing a MITM attack is less demanding — making this approach particularly dangerous.
Best Practices for Man-in-the-Middle Attack Prevention
With the threats explored, it is time to talk about neutralizing them. Below is our list of industry best practices for how to prevent man-in-the-middle attacks.
Monitor your network: Like many cyberattacks, man-in-the-middle attacks can create strange activity on your network. This makes constant monitoring essential to detecting and neutralizing these threats before they create significant damage. To that end, it may be a good idea to install an intrusion detection system (IDS) to help spot the initial signs of a breach.
Microsegment your endpoints: One of the best methods of neutralizing the threat of man-in-the-middle attacks is through endpoint security. The µGateway, built by Byos, is a comprehensive endpoint security solution that uses edge microsegmentation to put the user in a protected environment that’s isolated from the local network. Known as a “security stack on a stick,” µGateway runs a bi-directional firewall, prevents data leakage, and maintains direct and confidential communications with the network gateway without allowing the poisoning of routing tables.
Use secure connections: Although it does not guarantee safety, requiring your employees to only visit sites with an HTTPS connection using secure socket layer (SSL) technology is good practice. All they need to do is make sure the URLs of the sites they go to begin with “HTTPS.” While policies are one enforcement strategy, there are also browser plugins that ensure users only visit HTTPS websites.
Deploy multi-factor authentication: This security measure earns its keep when a user's credentials have been compromised. Multi-factor authentication requires users to confirm their identity beyond name and password through an additional route — often a text message. This means that even malicious actors with login credentials will not gain access to your systems.
Educate your employees: Many man-in-the-middle attack techniques depend on cybersecurity-naive target users to succeed. Email phishing, HTTPS spoofing, router spoofing, and other approaches do not work well against educated, alert users. So train your employees on the tell-tale signs of a scam: what to look for in a fake URL, why to avoid public wifi-networks, how to use a VPN, etc. Every person in your organization has the potential to slip up, so keeping them as threat-aware as possible improves your security profile.
Update your software consistently: Like educating your employees, this is another security fundamental. But that doesn’t make it any less important than the other items on this list. Failing to keep your software up to date creates unnecessary vulnerabilities in your tech infrastructure. So stay on the ball. This due diligence also includes the browsers your organization uses.
Employ WPA encryption: Protect your wireless access points with a robust encryption protocol. Anything less leaves your network susceptible to breach and a subsequent man-in-the-middle attack. So deploy WPA, WPA2, or WPA3 encryption. Preferably WP3, as it is the strongest of the mechanisms.
Next Steps for Man-in-the-Middle Attack Prevention
As complex and challenging as man-in-the-middle attacks are, the threat they pose is manageable with the right tools. That is why we built the µGateway, an all-in-one cybersecurity solution that protects your endpoints from man-in-the-middle attacks by creating a microsegmented network . If you would like to learn more, please reach out.