Cybersecurity threats in the healthcare sector continue to evolve. Knowing the techniques attackers commonly apply, like Man in the Middle (MITM), can help organizations prepare and protect themselves.
What are man-in-the-middle attacks?
An MITM attack occurs when a hacker secretly intercepts and possibly alters the communication between two parties who believe they are directly communicating with each other. A 2010 study found that in man-in-the-middle attacks, the scenario generally involves “ two endpoints (victims), and a third party (attacker). The attacker has access to communication channels between two endpoints, and can manipulate their messages.” The hacker can eavesdrop on the communication, steal sensitive information, and manipulate messages. For example, when you send your bank password, a hacker might capture that password, access your account, and even change transaction details.
When it comes to healthcare organizations, the stakes are even higher. Healthcare entities manage large amounts of personal health information that is confidential and highly valuable. Hackers target communications between doctors and patients or healthcare services, hoping to capture everything from patient records to login credentials.
The execution methods
MITM attack methods depend on the specific target and the attacker's objectives. Sophisticated attackers may combine several techniques to enhance the effectiveness of their attacks. For instance, an attacker might use ARP spoofing to get into a network and then employ SSL stripping to intercept and manipulate data. Multiple methods can complicate detection and increase the potential damage of the attack.
The execution methods include:
- ARP spoofing: In this case, actors may send fake Address Resolution Protocol (ARP) messages over a local area network (LAN). Hackers use it to link their MAC address with the IP address of a legitimate device on the network, effectively diverting all traffic meant for that device to themselves.
- DNS spoofing: Here, attackers manipulate the Domain Name System (DNS) to redirect traffic from a legitimate website to a fraudulent one. When a user tries to visit a particular website, they are routed to a malicious site that looks identical to the intended one, where the attacker can steal sensitive information.
- Wi-Fi eavesdropping: In this approach, attackers set up rogue Wi-Fi networks that appear legitimate. Unsuspecting users connect to these networks thinking they are authentic, and attackers capture the data transmitted over the connection.
- SSL stripping: This method downgrades a Hypertext Transfer Protocol Secure (HTTPS) connection to an insecure Hypertext Transfer Protocol (HTTP) connection. If connection security is compromised, attackers can view and modify the information exchanged between the parties.
- Session hijacking: Attackers use session hijacking to steal a session token by intercepting a session key that identifies the user to a server. Attackers can then impersonate the user and gain unauthorized access to the network or services.
Countermeasures
- ARP spoofing defense:
- Dynamic ARP Inspection (DAI) is available on modern switches and works by validating ARP packets in the network. DAI ensures that only valid ARP requests and responses are relayed.
- For specific systems, static ARP entries can be configured that do not change, which prevents ARP spoofing but is not scalable for large networks.
- DNS spoofing defense:
- DNS Security Extensions (DNSSEC) is a suite of specifications that secures the DNS lookup and response process. It ensures that the DNS responses are authenticated and have not been tampered with.
- Configuring firewalls and intrusion detection systems to monitor and block unusual DNS traffic can help prevent DNS spoofing.
- Wi-Fi eavesdropping defense:
- Use strong, up-to-date encryption protocols like WPA3 for Wi-Fi networks, which provide security against eavesdropping.
- Implement Network Access Controls (NACs) to enforce security policies for devices attempting to connect to the network, ensuring that only authorized devices can access network resources.
- SSL stripping defense:
- HTTP Strict Transport Security (HSTS) is a web security policy mechanism that helps to protect websites against protocol downgrade attacks and cookie hijacking.
- Session hijacking defense:
- Implementing timeouts for sessions and re-authentication for certain actions can reduce the risks of session hijacking.
See also: HIPAA Compliant Email: The Definitive Guide
FAQs
What is a VLAN?
Virtual Local Area Networks segregate devices within a network for improved efficiency and security.
What are NACs?
Network Access Controls are security measures that regulate who can access network resources, based on specific compliance and policy checks.
What is HTTP?
Hypertext Transfer Protocol is the foundational protocol for transmitting web pages over the internet.