What Is Spoofing & How to Prevent Spoofing Attacks in 2024? by Ben Martens

Ben Martens

Updated on: January 4, 2024

Spoofing is the act of faking a virtual identity for hacking or security purposes.

The most common types of spoofing include faking things like websites, caller ID, and email sender information, but there are also technically advanced attacks like IP, DNS, or ARP spoofing, all of which exploit server and network vulnerabilities.

Hackers use spoofing to steal personal information, gain access to your network, spread malware to your device, and/or attack servers and networks. But security tools and IT specialists also spoof user identities to protect themselves from surveillance tools and hackers.

Home users can’t prevent network-level spoofing attacks like IP spoofing and DNS spoofing, but they can minimize the risk of basic spoofing attacks to keep themselves safe from malware and network exploits that spoofers deploy. The best ways to prevent spoofing include using a network firewall, setting up two-factor authentication (2FA) for online accounts, using a secure web browser, and avoiding calls and emails from unknown sources.

How Does Spoofing Work?

Spoofing can be extremely technical… or fairly simple — it depends on the type of information that is spoofed. The most common types of spoofing include:

• Caller ID spoofing.
• Email spoofing.
• Website spoofing.
• IP spoofing.
• DNS spoofing.
• ARP spoofing.

Caller ID Spoofing

Area codes and caller ID names can be easily spoofed using voice over internet protocol (VOIP) apps, as well as ready-made spoofing apps and services. The call may appear as though it’s coming from your area code, someone in your contact list, a government agency, or a brand you trust, but it’s just an attempt to trick you into giving away private information.

Legitimate caller ID spoofing is common — lawyers, doctors, journalists, and even businesses spoof their numbers so that their calls remain private, or so that their clients don’t know that they’re calling from out of the office.

But especially recently, due in large part to the coronavirus pandemic, scammers have been taking advantage of people by spoofing health insurance companies, government health organizations, vaccine and testing clinics, and other legitimate healthcare operations.

In March 2021, Texas-based telemarketers John Spiller and Jakob Mears were fined $255 million for making over 1 billion robocalls in less than 5 months. They spoofed the caller IDs of well-known health insurance companies such as Cigna, Aetna, and Blue Cross Blue Shield, falsely offering short-term health insurance plans to scam people out of money and give up their personal information. Because according to US law, it is illegal to spoof caller ID “with the intent to defraud, cause harm, or wrongfully obtain anything of value.”

Email Spoofing

Email spoofing can be performed by creating a fake sender name or email address. Faking an email sender name takes advantage of the trusting nature of the Simple Mail Transfer Protocol (SMTP), which allows users to create their own “From” identity, regardless of their email address (US American users may recall receiving emails from dozens of different addresses labeled as “Joe Biden” or “Donald Trump” during the 2020 election).

Email spoofing can be as simple as replacing a letter or two from a legitimate email address, for example “support@amaz0n.com”, which replaces the letter “o” with a zero.

Spoofed emails are usually used for financial fraud, or to convince users to either download malware or visit phishing sites designed to steal user information. But privacy-seeking users and professionals also sometimes use a spoofed email address to keep themselves safe online.

In 2018, the city treasurer of Ottawa paid almost $100,000 to hackers who spoofed the city manager’s email address and requested a payout for an IT supplier based in the US. This kind of attack using spoofed emails is known as “whaling”, because it targets a single high-profile victim. For examples of general spoofing and phishing attacks, you can simply take a look at the “Junk” folder in your own email inbox.

Website Spoofing

To spoof a website, hackers create a domain name similar to the site they’re imitating (for example, www.usbank.wix.com) and then imitate the graphic design of the spoofed site. Once a spoofed site is finished, hackers lure users with phishing emails, smishing messages, pop-up ads, and even browser-hacking spyware. Spoofed sites can be used in phishing attacks, exploit attacks, malware attacks, or even just to generate ad revenue with pop-ups and clickbait-y banner ads.

In 2018, a security vendor discovered nearly 200 domains spoofing legitimate UK news sites such as BBC News, Sky News, and The Guardian. These fake sites were able to generate revenue from pop-up ads, collect user information by asking for login and financial information, and even install malware on users’ devices using exploit attacks and drive-by downloads.

IP Spoofing

All devices that connect to the internet have an Internet Protocol (IP) address that allows them to communicate with other servers and devices. Devices exchange data online by sending IP packets back and forth — for example, your computer sent an IP packet requesting a connection to geeksforgeeks.org, and our site responded by sending you a packet with the content of this article.

IP packets are prefaced with header messages that contain the IP address of the sender, along with other routing information, so that a server or router knows whether or not to accept the IP packets.

The information in these headers is all completely customizable — hackers exploit this flexibility by altering (spoofing) the IP addresses in the packets they send out. IP spoofing can be used in a distributed denial of service (DDoS) attack to overwhelm a server with requests from thousands of devices with spoofed IPs, preventing the server from being able to filter out legitimate traffic from spoofed traffic.

DNS Server Spoofing

DNS servers are kind of like the street signs of the internet — they translate web addresses (like geeksforgeeks.org) into IP addresses (like 2601:1c0:8101:7f70:a5e0:bf21:3bf3:7c37) in order to direct web traffic to its proper destination. Every time you search for a web address, your router requests the IP address for that website from a DNS server, which then connects your browser to the website.

Rather than searching the whole internet for an IP address every single time it gets a request from a user, a DNS server uses caches of known IP addresses — so every time a server is asked for www.geeksforgeeks.org, it can instantly connect the user to the proper IP address from its cache, saving time and processing power.

DNS spoofing, or DNS cache poisoning, seeks to insert false IP addresses into the cache so that the DNS server sends users to a different site than the user intends — kind of like a sign on the highway that has been forged to make users get off at the wrong exit.

A famous example of DNS cache poisoning is China’s Great Firewall — when you search for www.google.com in China, every DNS server in the country will think it’s sending your browser to Google, when in reality you’re being redirected to a dead IP address.

ARP Spoofing

ARP is similar to DNS, but it’s the protocol that decides where to send web traffic on your home network. Every device (computer, printer, phone, smart fridge, etc.) has a specific MAC address, which allows the device to be recognized by a router — the router uses ARP to figure out which MAC address requested web access.

ARP spoofing requires that an attacker has access to the victim’s local area network (LAN), either with a physical device connected to the victim’s network, or more commonly through compromising a computer on the same network as the attack target. This could be an IoT device, computer, smartphone, or anything that can be hijacked by malware.

ARP spoofing uses the same “cache poisoning” technique that DNS spoofing uses — the router thinks it’s sending web traffic to your laptop, but the traffic is actually being misdirected to a hacker’s device.

ARP spoofing attacks can result in stolen data, they can cause network crashes, and they can even be the first step in a man-in-the-middle attack where hackers are able to intercept and alter the communications in your LAN.

Common Signs of Spoofing Attacks

Due to the complex nature of ARP, DNS, and IP spoofing, I’ll focus here on less sophisticated techniques like caller ID, email, and website spoofing.

Here are some of the most common signs of spoofing attacks:

1. Unusual requests. It’s important to remember that doctors, banks, and businesses will never ask for your password or personal information via email. Any requests for you to re-sign into an account or share your personal information over text, phone, or email should be treated as a possible spoofing attack.
2. Bad grammar/spelling. Spoofing attacks are frequently carried out in countries with relaxed cybersecurity laws, by scammers with poor English language skills. Apart from poor English skills, email spoofers commonly replace one or two letters in an email, such as amaz0n.com or paypall.com, in order to trick users into thinking they’re visiting a legitimate site.
3. Urgency. Scammers frequently come up with scary and intense stories to urge users to immediately give up money or personal information quickly, so as to not give the user time to think about the legitimacy of the situation.
4. Sender name/email address discrepancy. It’s incredibly easy to spoof the sender name in an email. Just because it says “from: Tom Cruise” in your inbox doesn’t mean that the famous Hollywood actor is contacting you. Opening the email will reveal the sender’s true email address, which will often be completely unrelated to the supposed identity of the sender.
5. Links and attachments. Phishing attacks redirect users to spoofed websites using links embedded in emails and texts. If a message from a seemingly legitimate source is redirecting you to another website with a link, you need to be very careful about that site, as it could be a source of malware, exploit attacks, or just an attempt to steal your login information.

Best Ways to Prevent Spoofing Attacks

Use an Antivirus

Antivirus software like Norton 360 offer anti-phishing tools to detect website spoofing, and there are also internet security suites like Avira Prime that can detect caller ID spoofing on both iOS and Android.

Antivirus software also provides real-time anti-malware scanning, which can prevent spoofing attacks of all kinds from deploying malware onto your device. Many anti-malware programs also include secure browsers that can provide some protection against website spoofing by forcing HTTPS connections and using DNS over HTTPS protocols to prevent you from using unsecured websites.

Install a Firewall

Many of the best antivirus programs have a firewall to ensure your network stays protected by keeping unwanted intruders out.

A firewall monitors and filters all traffic that goes in and out of your computer or network. If an IP address is flagged as “spoofed”, the firewall will block it from entering the network or reaching your computer. Firewalls can also detect unusual network activity, which can help protect against ARP spoofing attacks.

Use Two-Factor Authentication (2FA) for Your Online Accounts

2FA enhances your account strength by requiring you to enter your password along with another piece of information before you can log into your online accounts.

That second piece of information can be a one-time password sent to your phone, a temporary one-time password generated by an authenticator app, a biometric scan, or a physical USB token.

If a hacker manages to get a hold of your password through a spoofing attack, they’d still need to use a second authentication method before accessing your account — and unless they also get a hold of your physical device or fingerprint, then your account will remain protected.

The top password managers on the market in 2024 all provide excellent 2FA compatibility to help strengthen online logins. Dashlane even includes its own built-in authenticator app.

Use a Secure Browser (or Harden Your Browser)

Chrome, Firefox, Edge, and Safari offer good protection against spoofing attacks, but there are more secure browsers out there. If you like your current browser more, you may consider getting some plugins to improve your online security.

For example, the Tor Browser bounces all of your web traffic through a network of encrypted servers, which will prevent hackers from accessing and hijacking your network for ARP attacks, while the HTTPS Everywhere plugin for Chromium and Firefox will force sites to use SSL/TLS encryption whenever possible, which can block phishing sites and network snoopers from intercepting and analyzing your web traffic.

If you want to know more about secure browsers, I recommend you take a look at our list of the safest and most private browsers in 2024.

Frequently Asked Questions

What’s the difference between spoofing and phishing?

Spoofing is the act of imitating a trusted individual, website, or web server using a variety of techniques.

Spoofing can be used both for hacking and security purposes — for example, a hacker may spoof caller ID to try to get your personal information, or a journalist from a repressive country may spoof their phone number to prevent the government from tracking them.

Phishing is a type of scam that makes use of spoofed email addresses and websites to convince users to give up money or personal information to hackers.

How does spoofing work?

There are many different types of spoofing, and they all involve a different set of tools. Here are some of the most common types of spoofing:

• Caller ID spoofing. Faked caller names and/or area codes, primarily used in financial fraud.
• Email spoofing. Faked sender names or email domains that are close to legitimate email domains (like @amaz0n.com), used to trick users for phishing, malspam, or exploit attacks.
• Website spoofing. Duplicated graphic design and login fields of legitimate websites, used for phishing, malware, or exploit attacks.

There are also a few more advanced kinds of spoofing, like IP address spoofing, DNS spoofing, and ARP spoofing that take advantage of holes in network security and limitations of general internet users.

Are spoofing attacks dangerous?

Yes, spoofing attacks are dangerous for individuals and businesses because they enable hackers to steal personal information, gain access to a network, infect devices with malware, and/or crash entire systems.

But there are ways to keep yourself safe from spoofing in 2024 — these include installing an antivirus, using two-factor authentication (2FA) to secure your online accounts, and using a secure web browser.

How do I detect spoofing?

When it comes to network-level spoofing, like DNS, IP, and ARP spoofing, it’s pretty hard for an everyday user to detect spoofing attacks. However, there are a few different things you can look for that could be signs of a spoofing attack:

• Poor spelling and grammar often indicates that the person isn’t who they claim to be.
• Unusually slow network traffic.
• Unusual banner ads, changes in website layout, or any cosmetic difference in a website could indicate that you are on a spoofed website.
• Unusual activity on your bank account.   

If you’re looking to keep yourself as safe as possible online, you need a comprehensive internet security solution. You can check out our list of the best antiviruses on the market, or even just try out Norton 360, which is available for a 60-day money-back guarantee.