What Is Spoofing? And How to Mitigate an Under-the-Radar Threat

In 2017, a man was arrested for stealing $100 million from two tech companies by launching an elaborate cyber attack. He didn’t use ransomware. And he didn’t use some kind of advanced, zero-day malware.

The attacker took an approach that typically gets less attention than the latest and greatest threats — it’s known as spoofing.

If you want to avoid becoming a victim of a similar attack, you need to know what you’re up against. But what is spoofing? And how can you take practical steps to protect your business from this type of threat?

What is Spoofing?

Spoofing is a type of spear-phishing attack where a malicious actor impersonates a device or user on your network to attack hosts, steal data, inject malware, and/or evade access controls to compromise your business.

Unlike phishing schemes that attempt to trick users into clicking malicious links or downloading infected attachments, spoofing focuses more on the duplication of an address to evade cyber defenses.

But not all spoofing attacks are created equal. The most well-known form is email spoofing, which is when an attacker disguises the “sender” field of an email to make a targeted user feel they’re communicating with a trusted source. In addition to email spoofing, these attacks can take the form of:

  • Caller ID Spoofing: More traditional spoofing attacks involved faking phone numbers so recipients believed the caller was trustworthy. Caller ID spoofing helps attackers evade initial suspicion so they can use social engineering to collect sensitive information.
  • Website Spoofing: Attackers mimic an existing website to steal login credentials from unsuspecting users.
  • IP Spoofing: Many networks authenticate users based on their IP addresses. By spoofing IP addresses, attackers can disguise their identities, access your network, and advance their threats. This type of spoofing is also effective for launching DDoS attacks.
  • ARP Spoofing: The Address Resolution Protocol (ARP) connects IP addresses to Media Access Control (MAC) addresses to transmit data. By spoofing your ARP, attackers can like their own MAC address to your internal IP addresses to act as a man in the middle, collecting data that was meant for users on your network.
  • DNS Server Spoofing: By spoofing your Domain Name System (DSN) servers, attackers can divert traffic on your network to different IP addresses that infect your network with malware.

What is Spoofing?

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Much like phishing schemes, spoofing is often used as a gateway tactic that initiates a larger cyber attack. Any of these types of spoofing can give attackers the access necessary to infect specific machines on your network, launch data breaches, execute advanced persistent threats, create footholds for man-in-the-middle attacks, and more.

To keep spoofing-related attacks from compromising your network, you need a workforce full of vigilant employees who are well aware of these potential threats. However, human error is a fact of life and you need to take additional, more practical steps to mitigate the spoofing threat.

Practical Steps to Mitigate the Threat of Spoofing

Attackers leverage spoofing to get behind your cyber defenses because they know that employees are the weakest link of any organization’s security posture. When employees trust a spoofed address, they essentially allow attackers to gain a foothold behind any perimeter security systems.

However, the following tools and practices can help you add an extra layer of defense behind your employees, mitigating the effects of spoofing:

  • Packet Filtering: When you can analyze individual data packets, your antivirus programs can filter out anything with conflicting a conflicting source address. This is especially useful for IP spoofing attacks.
  • Zero-Trust Approach: Traditional networking was all about trusted relationships between users and core systems. Attackers can spoof addresses to mimic trusted connections and compromise your network. But a zero-trust approach to security means all connections must be verified, which can help you weed out attackers.
  • Encryption: Embracing TLS, SSH, and HTTPS encryption across your network ensures that data is encrypted before transit and authenticated upon receipt, preventing spoofing opportunities from ever emerging.

Like any other threat, spoofing is a way for attackers to exploit vulnerabilities in your network. Defending against these threats can be challenging—but it’s not impossible.

The first step is to understand which vulnerabilities attackers might try to target when looking to compromise your network. If you want to learn more about your own weak points, take a look at our free vulnerability scanner.

About the Author

Joe Michalowski
Joe Michalowski
With a focus on cybersecurity, digital transformation, and IT infrastructure

About the Author

Joe Michalowski covers B2B tech topics including cybersecurity, digital transformation, IT infrastructure, and more.