What are DNS Attacks? How To Secure Your Digital Assets

If you’re reading this, there’s a good chance that your business has a website. To get to that site, you likely use something like YourBusinessName.com. This is made possible by domain name systems (DNS). 

Without DNS, every website would be a combination of numbers rather than easy-to-remember words! Your website is one of your important business assets, especially if customers can schedule and pay for services online. Which is why cybercriminals want a piece of that pie too. 

As hacking and other forms of online crime increase, it’s vital that you know about one of the most detrimental — DNS attacks. Here's how you can manage risks they pose to your organization. Having robust DNS security solutions in place is one of the best ways to mitigate the risk that these attacks can cause, particularly as hackers continue to become smarter at exploiting system vulnerabilities.

Typically, these attacks trick users into handing over personal or a business details through phishing or infecting their device with malware. Once hackers have this information, they can steal money, customer or business records, or even commit identity theft.

DNS attacks can cost businesses millions of dollars every year. With such valuable information at stake, it's no surprise that government agencies were among the most targeted organizations for DNS attacks in 2023, with figures suggesting a monumental 4,000% increase over 2022. That’s why it’s vital that companies understand how DNS attacks work and what can be done to avoid these risks.

How DNS attacks work

DNS systems are built on hierarchies within servers, storing information about website domain names, and their internet protocol (IP) address (location of where that website is based).

By typing in a domain name with correctly-configured DNS settings, the user’s browser will send a DNS query to the local DNS resolver, which looks up the associated IP address. From there, the query will be routed to the IP address, and the user will be directed to the correct website.

When a DNS attack occurs, vulnerabilities in this communication system are exploited by criminals. They intercept the query and send a fake response, redirecting the user to the wrong IP address. Depending on the type of attack, this manipulation can lead to stolen data or other malicious outcomes.

Types of DNS attacks

There are several different types of DNS attack which can be used individually or, in sophisticated attacks, combined to impact multiple areas of a business. Some of the most common are:

• DNS amplification: This is a form of distributed denial of service (DDoS) attack. Hackers flood the DNS resolver with excessive traffic using a fake IP address. The overload prevents legitimate users from accessing the real website.
• DNS spoofing: Also known as cache poisoning, in this attack, criminals manipulate a legitimate IP address and website to redirect the DNS server traffic to a fake or imposter site. The server caches the wrong IP address moving forward. When a user tries to access the real website, they’ll instead be sent to a clone site, allowing attackers to steal their personal information like login or payment details.
• DNS hijacking: Also known as domain theft, this type of DNS attack happens when criminals take over control of a domain entirely. They may steal login information from the website owner through other forms of DNS attack like spoofing, or exploit other vulnerabilities in the domain registrar system. Similar to spoofing, users are redirected automatically to a fake version of the original website.
• DNS tunneling: One of the most complex forms of DNS attack is tunneling, where cybercriminals are able to bypass firewalls and DNS filters to access data on an already compromised network. Data packets are sent to a remote network server to trick this server into thinking that this data is repeated legitimate DNS queries.

Impact of DNS attacks 

For companies that fail to protect their DNS infrastructure, the potential risks of a DNS attack can have significant and lasting impacts on the business. These include:

Loss of revenue

Besides the risk of losing financial records or, even worse, money itself from credentials stolen in a DNS attack, there’s also the possibility that these attacks can cause lasting issues for creating new revenue. 

Particularly in a DDoS attack where your site may be offline even for a short period of time, customers will be unable to make purchases online and may not return later to complete their transactions, which can result in long term revenue decline.

Regulatory issues

Industries like finance and healthcare, and even ecommerce businesses handle customer payments every day. A DNS attack can expose thousands of confidential records to cybercriminals.

Industries that are governed by strict compliance regulations will likely face significant fines, legal action, and long-term reputational damage as a result of a DNS attack and data breach.

Operational disruption

Critical functions within your business can be brought offline during a DNS attack. Not only does this impact your customers on the outside of the company, but it can also cause severe disruption within your organization. 

Internal operations going down result in decreased productivity and a backlog of work that needs to be completed once systems are restored.

Loss of customer and employee trust

When a customer works with you, they expect their information to be protected. Without this, your business’s reputation can decline rapidly, making it harder to retain existing clients or attract new ones in the future.

Not only is the reputation of your organization at stake to the outside world, but it can also erode your employees’ trust in you. Their personal information could be just as at risk as those of your customers when a DNS attack happens, particularly information held by HR. Rebuilding this trust both internally and externally takes significant time and money.

How to prevent DNS attacks 

How to prevent DNS attacks is a crucial step for individuals as well as organizations. Let's look at some best practices. 

For individuals

• Use a reputable DNS provider: Choose a provider with strong security measures.
• Enable DNSSEC: This cryptographic protocol validates DNS responses, ensuring their authenticity.  
   
• Keep software updated: Regularly update your operating system, web browser, and other software to patch vulnerabilities.  
   
• Use a VPN: A VPN encrypts your internet traffic, making it more difficult for attackers to intercept and manipulate DNS requests.  
   
• Be cautious online: Avoid clicking on suspicious links or downloading attachments from unknown sources.    

For organizations

Most DNS systems are built for functionality rather than security, which makes them easy targets for attack. With increasing numbers of cyberattacks occurring each year, it’s vital to take proactive steps to mitigate the risk to your business by implementing best practices such as:

• Privatizing DNS resolvers: Restrict access to the DNS resolvers to prevent cyber criminals from manipulating these parts of your system and gaining access to DNS records.
• Randomize source ports: By randomizing query source port on your DNS resolver, you can protect against cache poisoning and DNS attacks designed to overwhelm the system. Adding variability to all of your outgoing requests makes it more difficult for criminals to sneak a fake response into the system and it be accepted.
• Continually test for DNS vulnerabilities: Monitor your digital systems for any possibility of a bug or vulnerable point that could be exploited. Remember to update all antivirus and anti malware programs installed, as the most recent versions will typically offer protection against the latest DNS attack methodologies.
• Implement security extensions: A DNS security extension (DNSSEC) adds digital signatures to DNS records automatically, making it easier to verify the authenticity of an incoming DNS response. This is one of the best ways to protect against a cache poisoning attempt.
• Segment your networks: Separate your system networks into different configurations and on different servers to keep critical systems safe. This way, should a DNS attack occur, only the impact server will be affected and not the entire network.

Top 5 DNS security solutions

Using a DNS security solution is one of the best ways to filter DNS traffic, identify potential malware, and block suspicious activity coming through your DNS system. Businesses are able to protect employee endpoint devices as well as their own servers from harmful activity.

To be included in the DNS security solutions category, platforms must:

• Identify and block high-risk traffic at the DNS level 
• Monitor traffic for dangerous sites and scan content for malware 
• Facilitate the classification of end users, endpoints, and digital content

* Below are the top five leading DNS security software solutions from G2’s Summer 2024 Grid Report. Some reviews may be edited for clarity.

1. Cisco Umbrella

Cisco Umbrella provides high-compliance security solutions in a single, cloud-native solution. With DNS-level security and secure gateways, your business data is protected by one of the world’s most powerful cyber threat intelligence teams.

What users like best:

“Cisco Umbrella offers an intuitive and easy-to-use management platform. The policies are easy to build and construct, and deploying to on-prem and mobile users can be done in a matter of minutes.”

- Cisco Umbrella Review, Kevin A.

What users dislike:

“I would prefer if there were some changes to the UI and ease of access. It was kind of daunting to use it at first, as I found the learning curve to be quite steep.”

- Cisco Umbrella Review, Aman V.

2. Cloudflare Application Security and Performance

As the world’s first connectivity cloud, Cloudflare Application Security and Performance provides security solutions for all your web applications and APIs, no matter where they’re hosted or where your users are based. The software has an easy to use interface, where you can integrate and manage multiple applications at once.

What users like best:

“The best part about Cloudflare CDN is their generous free tier plan that helps indie developers to start with and experiment with things.”

- Cloudflare Application Security and Performance Review, Anubhav G.

What users dislike:

“I found it a bit technical. Your website may be down if you make any changes without knowing the consequences. Also, I migrated my domain to Cloudflare and I feel that some of my DNS records are missing.”

- Cloudflare Application Security and Performance Review, Manish S.

3. DNSFilter

DNSFilter is an industry-leading DNS threat protection and content filtering tool. Powered by machine learning and AI, this software offers protection against malware, ransomware, and phishing attacks on DNS systems for companies of all sizes.

What users like best:

“I like how easy it is to script the installation on client computers. It has prevented my users from accessing sites registered in the last 30 days which has helped to prevent a phishing scam.”

- DNSFilter Review, Chris R.

What users dislike:

“VPN use with the agent is a hard no. It causes issues with users being able to access sites they normally would be able to. Support does not give a work around for this.”

- DNSFilter Review, Matt C.

4. Infoblox NIOS

Whether your assets are in the cloud or stored in your datacenter, Infoblox NIOS gives you greater control over your network settings and security protocols. This software can be integrated into any network environment, making it quick and easy to protect your most valuable business data.

What users like best:

“Infoblox NIOS provides visibility across your network by consolidating data from DNS and DHCP services and eventually forming what they called the "single source of truth." which is the IPAM. It is easy to use in management since all configurations must be done on a single platform, even without direct access to appliances distributed across the network.”

- Infoblox NIOS Review, Mark Razel M.

What users dislike:

“The licensing cost should be waived for the primary platform, all other services also involve a cost for licensing.”

- Infoblox NIOS Review, Anvar A.

5. BloxOne DDI

BloxOne DDI is a DNS firewall that gives you proactive network protection against new and evolving malware threats. This tool provides security against DNS-level threats, allowing you to control and manage your security measures in a cloud-based environment.

What users like best:

“Ability to detect viruses communicated by DNS servers together with the DHCP service. Automatic blocking of communication from a program or device to an Internet connection, detection of domains, known IPs of malware, theft of information and identities.”

- BloxOneDDI Review, Jake M.

What users dislike:

“Pricing of this solution is too high and is not affordable for small level organizations. The in-house model has a very high price which is not a good solution for small level organizations.”

- BloxOne DDI Review, Zeeshan A.

Frequently asked questions (FAQs) on DNS attacks

How do DNS attacks work?

DNS attacks can be carried out through various techniques, such as:

• DNS poisoning: Injecting false DNS records into DNS resolvers. 
• DNS spoofing: Intercepting DNS requests and sending fraudulent responses.
• DNS hijacking: Taking control of a domain name or DNS server.

What are the consequences of a DNS attack?

DNS attacks can have severe consequences, including: 

• Financial loss: Phishing attacks, malware distribution, and fraudulent transactions.
• Data breaches: Exposure of sensitive information. 
• Reputational damage: Loss of trust and customer confidence.
• Service disruption: Interruption of critical online services.

How can I protect myself from DNS attacks?

To protect yourself from DNS attacks, you can:

• Use a reputable DNS provider with strong security measures.
• Enable DNSSEC to validate DNS responses.
• Keep your software and devices up-to-date.
• Be cautious of phishing attacks and avoid clicking on suspicious links.
• Use a VPN to encrypt your internet traffic.

What is an example of a DNS poisoning attack?

An example of a DNS poisoning attack could be redirecting users to a malicious website instead of a legitimate one. For instance, an attacker might poison a DNS resolver to redirect users from "[invalid URL removed]" to a fake website that looks like Google but is designed to steal user credentials.

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DNS attacks continue to pose a significant threat to online security for businesses of all sizes. By proactively addressing how you could mitigate these risks with strong protection measures, you can keep your vital business assets safe in this ever-changing world of cybercrime. 

Monitor your web traffic and stop a DNS attack before it happens with DDoS protection tools that deflect malicious attempts to infiltrate your network.

Edited by Monishka Agrawal