Guide for Preventing Man-in-the-Middle Attacks

Some of the most devastating cyberattacks do not rely on brute force but instead succeed through stealth. These quiet intrusions often go unnoticed until long after the attacker has disappeared. Among the most insidious are Man-in-the-Middle (MITM) attacks, where criminals exploit weaknesses in communication protocols to silently position themselves between two unsuspecting parties. Fortunately, protecting communications from MITM attacks does not require complex measures. By taking a few simple steps, security teams can significantly enhance user data protection and keep silent attackers at bay. In a MITM attack, a malicious actor intercepts communications between two parties, such as a user and a web application, to steal sensitive information. By secretly positioning themselves between the two ends of the conversation, MITM attackers can capture data like credit card numbers, login credentials, and account details. This stolen information often fuels further crimes, including unauthorised purchases, financial account takeovers, and identity theft.

MITM attacks are especially common in environments with unsecured Wi-Fi and a high volume of potential victims, such as coffee shops, hotels, or airports. Cybercriminals exploit misconfigured or unsecured networks or deploy rogue hardware that mimics legitimate access points. Once the rogue access point is active, the attacker spoofs the Wi-Fi name, known as the Service Set Identifier (SSID), to closely resemble a trusted network. Unsuspecting users, whose devices automatically connect to familiar or strong-signal networks, often join without realising they are on a malicious connection. Spoofing plays a crucial role in MITM attacks, allowing attackers to disguise themselves as a trusted entity within the environment. This deception enables them to intercept, monitor, or manipulate the data being exchanged without raising suspicion. Common tactics include mDNS and DNS spoofing, which trick devices into trusting malicious sources. Attackers exploit mDNS on local networks by replying to name requests with fake addresses, while DNS spoofing injects false data to redirect users to harmful websites, where sensitive information can be stolen. Additionally, hackers may intercept local network traffic by exploiting the Address Resolution Protocol (ARP). By replying to a device’s request for a MAC address with their own, attackers redirect data meant for another device to themselves, allowing them to capture and analyse private communications, potentially stealing sensitive information.