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Everything You Need to Know About DNS Security

By October 23, 2019No Comments6 min read
DNS Security dns firewalls

You might have heard about DNS firewalls. There are many benefits of using DNS firewalls. But, first, you must understand how DNS works. The DNS is the soul and heart of the whole internet. It is like a phonebook that your computer uses to map hostnames to IP addresses. Without DNS your computer can’t interact with online services like a website. It is used for matching server hostnames to their IP addresses. Your browser will send a query to a DNS server which will provide the correct IP address.

DNS system wasn’t introduced as a secure protocol in the 1980s. Only a few people had an idea about public-key cryptography and another security mechanism. All the networks have a very limited number of users. Thus, there was no need to have a secure protocol. But, the Internet has grown tremendously in recent years. More than half of the world is connected to the internet. Servers are rapidly increasing every day. Thus, the DNS system was used by a large group of people. Millions of servers were using DNS for mapping their server with IP addresses. But, it wasn’t fully secured.

Today we are going to talk about how to protect your server against common DNS attacks. But, before that, you must understand how a DNS attack works.

How do attackers attack the DNS infrastructure?

The DNS service is one of the oldest Internet services. But, still most of the Network Administrator, DevOps and SysAdmins forget to increase its security. Most of the Network administrator only focuses on web servers, SSH services, and database systems.

If your DNS configuration is lacking proper security, then it can lead to some serious problems. Hackers can exploit the system to perform attacks like changing DNS zones. They can even modify the DNS resolvers. If your DNS resolver is modified, then it will report to different IP addresses. Hackers can use it to scam your enterprise customers. They can even some dangerous attacks like DNS amplifying attacks.

Your customers don’t have any way to check if they have been redirected to some other server. Their emails will be sent to the attacker’s inbox. Thus, they will get confidential data related to your enterprise. This is why you should always keep your DNS secured.

How to prevent DNS attacks?

  1. DNS firewall

DNS firewall is the best method to prevent DNS attacks. It has been around here for more than 20 years. But, most of the administrators are implementing them now to safeguard their servers. If you are using DNS firewalls, then your query will be evaluated by the DNS server. It will check the IP address, hostname and compare it with a list of threats. If the query is safe, then DNS will return the IP address. If any threat is detected, then DNS will automatically redirect you to a verification landing page. DNS firewalls are one of the best ways to prevent a DNS attack. It provides various benefits to both end-users and enterprises. DNS firewalls can solve enterprise problems like:

  • If your enterprise has multiple offices, then you can monitor threats from a single place.
  • All DNS traffic will be redirected to the same location. Thus, you can easily track DNS traffic.
  • If you have remote workers, then DNS firewalls are more important for you. You don’t know where your remote workers are working from and what websites they are visiting. By using a DNS firewall, you can control the content that your remote workers can access.
  1. Update your DNS servers regularly

If you are running your own name server, then you have the power to test, configure and try different things. You can’t change the configuration of your private servers that your hosting provider will give. There are various tools like PowerDNS, Microsoft DNS, and BIND that you can use to run your own DNS servers. If you are using these tools, then it is very important to keep them updated. Make sure to download every security patch.

All the latest versions of DNS servers already contain security patches against known threats. They also support various security technologies like RRL and DNSSec.

  1. Buy DDOS protection services

You can easily mitigate small DDOS attacks by tweaking HTTP services and network filters from your operating system. But, only a few Data centers can protect their customers from a big DDOS attack. If you are running your own DNS server, then a DDOS attack will shut down your server for a long period. Thus, it is always best to hire an anti-DDOS specialized server like Akamai, Incapsula or Cloudware. These servers will help you in dealing with DDOS attacks. Hence, your DNS server will always be running.

  1. Two-factor Authentication

If you are using third party DNS services like DNSMadeEasy and Cloudflare DNS, then their servers are already secured. However, no one can protect your account from getting compromised. Thus, it is best to use two-factor authentication to protect your account from hackers. This will make sure that hackers can’t access your account even after getting your password and username. This is the final tip that you can follow to avoid a DNS zone compromise. You can also use Google authenticator instead of SMS verification. Google authenticator is more secure when compared to SMS verification.


Attackers will always try to target your enterprise services. They will always try to find some weakness in your Domain Name System. Thus, you must have a solid DNS security policy that will help you to avoid most of the DNS attacks. One of the best methods to prevent DNS attacks is by using DNS firewalls. It will also protect your server from attacks like cache poisoning and DDoS. You can easily implement these DNS firewalls. If you need more information regarding DNS security, then you can reach out to experts working at Bleuwire.

Contact us today to learn about Bleuwire™  services and solutions in how we can help your business.