Internet is an indispensable part of a modern digital business. Moving data to the cloud and operations online brings considerable convenience, efficiency, and profitability. At the same time, having mission-critical, sensitive information traversing the internet also brings obvious security risks.
One of the oldest and commonly used attack tactics to intercept traffic and steal precious information on the internet are man-in-the-middle (MitM) attacks. The reason why MitM attacks are so prevalent is that they are easy to launch, hard to detect, and provide real-time access to precious data. Besides, man-in-the-middle attacks also serve as launchpads for hackers to infiltrate broader core IT networks.
Given the nature of man-in-the-middle attacks, they can have a serious impact both at an individual and at an organization level. Understanding the cause of these attacks and taking preventative security measures can greatly help keep data and digital infrastructures safe.
What Are Man-in-the-Middle (MitM) Attacks?
When two genuine parties are conversing, a malicious actor places himself in between the conversation without either party being aware of it. The conversations can be between a user and a machine (such as the browser-server communication) or between two machines. When successfully executed, the hacker can:
- Eavesdrop on the conversation and steal information that passes through
- Insert malicious links such as Trojans to alter the contents of the message, impersonate either party and trick the target into revealing sensitive information.
Man-in-the-middle attacks are usually launched to harvest personal information such as login credentials, account information, and credit card details that can be used to manipulate the victim’s online activities or blackmail for ransom. Banks are especially susceptible to MitM attacks owing to high-value transactions. Think of cybercriminals preying on unsuspecting users, monitoring their communications, and carrying out illicit money transfers. Because attackers masquerade as genuine communicating parties, in most cases, users are completely unaware that they are being attacked. That’s the gravity of impact MitM attacks can unleash.
While financial institutions are still the primary targets, MitM attacks are quickly spreading across various other industries investing in digital services and transactions. The increased proliferation of IoT in medical equipment is bound to escalate MitM attacks in the healthcare sector.
What Causes Man-in-the-Middle Attacks?
From email to IP address to WiFi, hackers employ several techniques to launch man-in-the-middle attacks. One of the widely used techniques amongst all is SSL/TLS.
SSL/TLS certificates are the very foundation of internet security. Built on public key cryptography, they help authenticate and encrypt communications to protect data at rest and in transit. However, attackers have found various ways of manipulating or bypassing the encryption mechanism to intercept communication.
Mainly, there are three ways man-in-the-middle attackers exploit SSL/TLS encryption:
1. HTTPS Spoofing
This is also referred to as a phishing attack where a hacker builds a look-alike website by spoofing the address of the genuine business website. Then unsuspecting users are tricked into visiting the fake website and revealing information. Therefore, exposing themselves to the attack.
2. SSL Hijacking
SSL hijacking involves a hacker stealing the session key to gain unauthorized control over the user’s session. The hacker masquerades as the legitimate user and manipulates the communication without the user or server being aware of it.
3. SSL Stripping
SSL stripping attacks involve the attacker downgrading a web connection from secure HTTPS to the less secure HTTP version of the same website. As the HTTP version does not encrypt data, the attacker can read all information exchanged between the server and the client.
4. BEAST (Browser Exploit Against SSL/TLS) Attacks
It is essential to understand that the strength of data encryption directly depends on the efficacy of the SSL/TLS protocol. When certificates use outdated or deprecated TLS protocols, the strength of encryption is severely affected, allowing MiTM attackers to launch BEAST attacks. These attacks are facilitated by weak cipher vulnerabilities in older TLS protocols such as TLS 1.1. Weak ciphers are easy to break and allow hackers sniffing encrypted traffic to extract pieces of information without actually decrypting the data stream.
How Can You Prevent Them?
There are several security best practices that organizations can follow to prevent man-in-the-middle attacks. Some of these include:
Virtual Private Network (VPN)
VPN connections are a secure choice while connecting to the enterprise network over public networks. A VPN creates a subnet and encrypts the connection between two parties for secure data transmission. So, even if MitM attackers manage to access the shared connection, encryption prevents them from intercepting the information.
Multi-Factor Authentication (MFA)
Multi-Factor Authentication systems operate on multi-layered access that requires two or more forms of identity verification. In the case of MitM attacks, MFA can help perform identity verification beyond the simple login credentials. This involves using secret pins and one-time passwords that require users’ input. Having extensive verification through MFA prevents hackers from using the first set of stolen credentials as access cards for data theft.
Public Key Authentication
Public key infrastructure or PKI is a widely used framework in internet data security. It rests on the concept of authenticating communicating parties using digital certificates and encrypting their communication using cryptographic keys. Implementing PKI-based security controls helps secure access to digital assets as well as secure data that is exchanged. SSL/TLS is based on public key authentication and allows websites or applications to only establish secure HTTPS connections that are too hard to break.
Since MitM attacks abuse weaknesses in SSL/TLS certificates, focus on the proper implementation of the SSL/TLS protocol. Identify certificates that use weak TLS standards and upgrade them to the latest and recommended standard. Renew weak certificates with new and safer standards to ensure encryption stays robust and data transmission secure.
Authentication is another element that is key to preventing man-in-the-middle attacks. Having always-on authentication helps users verify the credibility of a website and steer clear of MitM-driven fake websites. To ensure authentication is never interrupted, always plan to renew certificates well before their expiry dates.
Prioritize PKI for Stronger Internet Data Security
Today’s complex IT infrastructures are highly complex, hosting thousands of digital assets. Protecting these digital assets and their communications require strong PKI-based security controls. PKI is also continuously evolving and adapting to meet the security requirements of a cloud-driven world. However, managing digital certificates and keys for every asset connecting to the internet is easier said than done. The problem is especially pronounced when digital certificates and their lifecycles are managed manually.
Manual certificate management is tedious and susceptible to errors. It does not provide sufficient visibility into distributed certificates, making it difficult to identify vulnerabilities and remediate them. Renewal and provisioning certificates can also be extremely challenging as this would involve several manual checkpoints. This is where an automated certificate lifecycle management (CLM) system proves indispensable.
An automated CLM system abstracts the complexity of certificate management and provides an easy-to-use framework for public key infrastructure (PKI) teams to perform lifecycle functions. It helps establish well-defined processes, enforce uniform policies, and standardize certificate management across the enterprise. By automating CLM, organizations can gain top-down visibility of the entire PKI, save time spent on repetitive manual processes, eliminate expiry-related security incidents, and also improve compliance.
While PKI is built to offer strong data security, it works best when it is supported by a modern-day automated CLM solution.
The Last Word
Man-in-the-middle attacks are becoming increasingly popular among hackers. With digital assets exploding, there is an ocean of opportunities for hackers to use MitM tactics. Sometimes, all it takes is one weak TLS certificate to cause a big data breach. While sophisticated attacks may be too difficult to thwart, attacks such as MitM can certainly be prevented, and it starts with adopting a preventative approach and reinforcing the right security measures.