A man-in-the-middle (MITM) attack happens when a bad actor intercepts traffic as it’s transmitted from point to point. The cybercriminal may be simply listening to network traffic, or they may also engage in active eavesdropping on communication and data transfer. They can then modify the traffic for malicious purposes, without either party (usually a service/system and a user) becoming aware that the link between them has been compromised.
Cybercriminals launch MITM attacks to steal personal information, including credit card details, account numbers, and other credentials. Financial institutions are usually primary targets because of the sensitive data they handle. Information stolen during an attack can serve many purposes, including an unauthorized password change, fund transfers, or even identity theft. Furthermore, the information stolen can help the bad actor gain a major foothold during the infiltration phase of an advanced persistent threat (APT) assault.
An attacker first intercepts traffic sent through the network before it reaches its intended destination. The simplest way for someone to intercept data is by eavesdropping on a user who logs onto an unencrypted Wi-Fi connection. These hotspots offer no guarantee of security and aren't password-protected, displaying a name relevant to their approximate location and inviting anyone to connect. Once someone does, the attacker can monitor the ongoing data exchanges.
Cybercriminals seeking more targeted data might launch an active attack through various ways:
After an attacker intercepts data, they must decrypt it without alerting the service or user. There are several ways to accomplish this:
In the financial services sector, notable examples of MITM attacks include:
One of the most disconcerting aspects of an MITM attack is that it can be challenging for any security team to detect for a long time. Therefore, it's essential to take the necessary steps to prevent an attack rather than try to remediate an existing problem. To protect their people and processes, financial organizations should adopt methods designed to prevent attacks from occurring in the first place.
If employees don't follow the rules, even the most comprehensive security policies will fail to prevent unauthorized access. Cyber awareness training helps fill in the gaps to give employees a complete view of possible threats, what to look out for, and what to do or what not to do.
Cybersecurity training is not a one-time thing; all employees, experienced or new, from junior teams to management, should undergo regular training to stay up-to-date on the latest security protocols. Some aspects to cover in this training include:
A company's security is only as strong as the weakest link. Therefore, training sessions should be mandatory and include exercises to test employees' knowledge; an in-house security team or third-party experts can lead the training.
Adopting a zero trust architecture further enables financial organizations to defend against the growing threat of man-in-the-middle attacks. Zero trust means trusting no device or user—inside or outside an organization’s perimeters—without verification. Because it relies on continuous verification across every device, user, and application, this architecture makes it more difficult for cybercriminals to pretend to be someone else because they will need to prove their identity to access the network in the first place.
Machine intelligence should also be an essential part of any company's cybersecurity strategy. Recent machine-intelligence advances have allowed organizations access to a new line of defense against even the most sophisticated cyberattacks. These systems scan all messages sent on a company's network and compare them with standard behavior patterns. By documenting every interaction that employees share, they understand which lines of communication are typical and under what circumstances. Should a message fall outside the normal behavior parameters, these systems will flag it as an anomaly and possible threat. This ongoing monitoring can help organizations identify suspicious behavior and emerging threats that human eyes wouldn't see.
To find out more about how you can protect your organization against man-in-the-middle attacks, download for free The Clear & Complete Guide to Smarter Email Security: