DNS spoofing explained: what it is, how it works, and how to mitigate it

 

When your customers or clients type your website in the address bar, the internet does not recognize it as “yourcompany.com”; it actually looks for the numerical IP address that corresponds to that name. This happens through the Domain Name System (DNS), which is essentially like a directory of the internet.

Well, the entire process of your clients typing your website into their browser, sending a request to the DNS, and being directed to your server is pretty quick and seamless. But it is only until a cyber attacker intervenes that things start to go wrong. 

What they do is, they manipulate the directory itself, which is the very system that tells the browser where to go. This is called DNS spoofing. 

Normally, when someone types yourcompany.com, the DNS tells their browser where your real server is. But when attackers interfere, they alter that information, sending users to a fake website that looks just like yours. Once the user lands on the fraudulent website, the attacker can do almost anything: steal passwords, hack systems, or even collect credit card information.

In this article, we will dig deeper into how DNS spoofing works, what makes it so dangerous, and how you can protect your business from it.

 

 

What is DNS spoofing?

All your domain-related information, such as website names, IP addresses, and mail server details, is stored and managed through DNS. But unfortunately, it is not as secure as you think. (After all, it is not designed for security)

For attackers, DNS is the real gold mine as it controls where internet traffic goes. And if they manage to alter or “poison” DNS data, they can easily redirect users from your real website to a fake one, which is under their control.

This is called DNS spoofing or cache poisoning. In this type of attack, the attacker changes the DNS information so that when someone tries to visit your website, they are sent to a fake site instead. To make things worse, they make sure that the fraudulent website mimics the legitimate one so that the users don’t second-guess before entering their information. 

Once the user trusts the fake website and enters their details, the information goes straight to the attacker and can be misused for malicious purposes. This is alarming not just for the users but also for your business because it puts both at risk. When attackers steal user data through a fake version of your site, it not only harms your customers but also jeopardizes your brand’s trust and reputation. Even if your real website is secure, people will still associate the breach with your business.

 

 

How does DNS spoofing work?

Understanding what goes on behind the scenes in DNS spoofing is just as important as understanding the attack itself. This will help you identify any gaps in your setup and plug them before the attacker leverages them. 

Here are a few ways in which an attacker can make the DNS give a wrong response to the browser:

 

Classic cache-poisoning

In a cache-poisoning attack, the attacker tricks a DNS resolver into storing a false IP address for a domain. After that, anyone who asks that resolver for the domain gets the wrong IP and is sent to the attacker’s site. 

 

Local network manipulation

Another way that an attacker can alter the DNS response is by manipulating the local network. If someone is on open Wi-Fi or a compromised LAN, the attacker can trick their device into thinking that their computer is the router. This is called ARP spoofing. This type of attack is fairly common on public Wi-Fi networks, like in airports, cafes, or libraries. 

Once the attacker is in the middle, they can intercept your internet traffic and send fake DNS answers. This means that even if you type the correct website name, you’re sneakily sent to a fake site instead. 

 

 

Compromising the authoritative DNS server

If an attacker manages to get into your authoritative DNS server, they can wreak havoc by changing your domain’s official records. They can point your website, email, and other services to fake servers that they control. This means users who try to reach your site will unknowingly land on a fraudulent one. It allows attackers to steal data, disrupt business operations, or even take your site offline.

 

What are the consequences of DNS spoofing?

What happens when your domain isn’t secure enough and the attackers spoof the DNS? In such cases, your business and your customers can suffer in several serious ways. 

Let’s take a look at how: 

 

Loss of Data

As soon as attackers gain access to your DNS, the first thing they eye is the critical data that is stored within it. By tampering with these entries, they can have access to your business’s entire digital infrastructure, redirect users to malicious sites, and even steal their credentials or other sensitive information.

 

Installing malware into your users’ systems

When attackers redirect your clients to their malicious sites, they do it to disrupt normal operations and gain hidden access. So, the fraudulent page that users land on will ask them to download a file (shown as an update, invoice, or document) or exploit browser flaws to install software without seeking any permissions. This installs malware on their systems, and once malware is on the device, it can steal passwords, record keystrokes, send sensitive files to the attacker, or create a backdoor so the attacker can come back later.

 

Disrupt any important security updates

Spoofing your DNS also means that the attackers can disrupt or block important security updates. They can redirect your systems to fake update servers that never send real patches, or worse, send infected files instead. This stops your computers and servers from getting the latest fixes, leaving them open to known security flaws. Over time, this makes it much easier for hackers to attack again or spread malware.

 

 

Censorship

Another major consequence of DNS spoofing is censorship. By altering or blocking your DNS records, the attackers can control what websites people can access. For instance, in countries like China, the government alters the DNS so that only approved websites open while others are blocked. This prevents users from reaching it rather than blocking it altogether.  

 

How can you prevent DNS spoofing?

Now that you know what DNS spoofing is and how it can impact your clients and your business, the next step is to take proactive steps to mitigate it. 

Protect your domain from DNS spoofing with SPF, DKIM, and DMARC — essential email security tools that verify sender authenticity and prevent phishing attacks.

Here’s how you can reduce the risk of DNS-based attacks:

 

Detection before it’s too late

Early detection is the key to mitigating the risk of DNS spoofing. One of the most effective tools for this is DNSSEC (Domain Name System Security Extensions). DNSSEC adds an extra layer of security by ensuring that the responses are authentic and not tampered with. It does this by digitally signing DNS records, ensuring that no one has tampered with them during transmission. It also keeps the data safe, allowing only trusted systems with valid access to read it.

 

 

Thoroughly filter your DNS traffic

If you let anyone and everyone send DNS queries to your servers, you make your DNS vulnerable to attacks. This is why it is important to keep track of all the DNS requests that enter and leave your network. This helps you identify any suspicious requests before they can cause harm. You can do this by using a firewall or security software that can inspect DNS requests and decide which ones to allow or block.

 

Regularly patch the DNS server

Keep your DNS server up-to-date. Hackers are always on the lookout for outdated software, which they can easily exploit and gain access to. So, when you install the latest updates and security patches, you fix those weak spots before they can be used against you.

 

Use VPN

While accessing a website or a page, if you can’t connect through HTTPS, make sure you use a trusted VPN. A VPN creates a secure, encrypted tunnel between your device and the internet, hiding your data from attackers and even your Internet Service Provider (ISP). This means, with VPN turned on, the attackers won’t be able to see which websites you’re visiting or what information you send or receive. It’s especially useful on public Wi-Fi, where DNS spoofing and data theft are most common. 

 

 

Final words

Unfortunately, DNS is not inherently secure. And with grave cyberattacks like DNS spoofing, even a small vulnerability can be exploited to cause major damage. Attackers can manipulate DNS data, redirect your users to fake sites, steal sensitive information, and harm your brand’s credibility, all without hacking your actual website. That’s why securing your DNS should be your top priority. 

If you’re not sure where to start, reach out to our team of experts! They will help secure your DNS setup and protect your online presence from potential spoofing attacks. Not just this, we’ll also ensure that your digital infrastructure is fully protected with the right security configurations, continuous monitoring, and timely updates. Contact us today to get started!