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DNS-Layer Security protects users from threats that arise from inbound and outbound traffic. It refers to monitoring communications between endpoints and the internet at a DNS-layer level.
Imagine the DNS layer security as a gatekeeper who makes sure that all potentially malicious visitors remain at the gate. But that`s not all. The gatekeeper keeps an eye on how allowed visitors behave once they get inside and also on whoever claims to exit the gate. Content filtering and domain categorization are examples of DNS layer protection methods.
At the moment, most companies still ignore the benefits that DNS security would bring to their security strategy. But this is about to change. Cyberattacks become more and more complex and the costs of data breach consequences are rising.
For a long time, businesses focused on antiviruses to detect and respond to threats that had already penetrated their systems. A strong antivirus that blocks known threats is a must-have, but it can only help your team detect and block malicious activities that others already confronted.
So, the company will still lose resources that could have been safeguarded. How? By enforcing a DNS layer security solution to block the threat before it penetrates the system.
Why Is DNS Layer Security Important?
Researchers say 91% of cyberattacks are conducted by leveraging the DNS. When a threat actor downloads malware in a network and then communicates with a C&C server to exfiltrate the stolen data, he uses the DNS.
When he puts up a phishing campaign, he patiently waits for an unsuspecting employee to click on the malicious link. Once again, he uses the DNS. These two examples alone show clearly why DNS protection is critical.
DNS, the famous Yellow Pages of the Internet, was not created with security in mind. Cybersecurity was simply not that big of a problem back then. This left the DNS that we daily rely on to do our jobs, pay our bills, find out what our relatives and friends are doing, etc. highly vulnerable to attacks.
Not minding securing it equals leaving the gate largely open to all sorts of malware, ransomware, and phishing attacks that your antivirus might or might not catch in time.
Enforcing security policies to track unusual DNS behavior and filter traffic enhances network protection and improves the detection of malicious activity at an endpoint level.
How Is DNS Used in Cyberattacks?
While DNS aims to translate machine-readable addresses to human-comprehensible domain names, it is also a threat actor`s predilect tool for cyberattacks. There would be no Internet connectivity without DNS.
While daily activities become more and more digitalized, using the Domain Name System is something you simply can`t avoid. If left unprotected, adversaries can easily use DNS in malicious ways. Hackers seized the opportunity and came up with two main ways of leveraging DNS for cyberattacks:
- Denial-of-Service – DoS and DDoS attacks
Threat actors flood a DNS server with traffic aiming to make it unavailable to its legitimate users and even take it down. DoS attacks vary according to the vulnerability or protocol\system\code limitation they use. DDoS, which stands for Distributed Denial of Service, employs botnets to launch DoS-type attacks on large targets.
- DNS Hijacking
In this case, the threat actor manipulates a DNS query’s resolution and redirects it to a compromised DNS server. Unsuspecting visitors will come upon an infected website. This is also known as DNS poisoning or DNS redirection. DNS spoofing, also known as DNS cache poisoning maliciously directs the victim to a forged website built by the hacker.
DNS tunneling is another malicious way of leveraging the phone book of the Internet. Through this technique, which is not harmful per se, hackers manage to send malicious data avoiding network filters and firewalls. Threat actors use DNS attacks for phishing campaigns, deploying malware and ransomware, and exfiltrating data.
Main Components of DNS-Layer Security
With time, it became obvious that unsecured DNS servers were both a target and a way of conducting malicious activities. As more and more businesses started to use the Internet, a new challenge arise – the need to secure the DNS. So, security specialists had to find innovative solutions to the increasingly disrupting DNS security problem.
Years later, DNS-layer security is a worldwide recognized practice and is based on two main components.
- Domain Name System Security Extensions (DNSSEC) is the most basic form of DNS security. DNSSEC was meant to defend Internet users against fake DNS data by using an embedded digital signature. DNSSEC checks the DNS query responses before communicating them to the client. The data is verified through a system of public keys and digital signatures. Public key cryptography is the basis of DNSSEC validation.
- DNS filtering, also known as DNS firewall or DNS blocking, is a method of preventing access to potentially malicious domains. Every time a user issues a DNS query, the DNS filtering solution uses a blacklist of malicious domains or IP addresses to check if the requested website is harmful. If the domain is on the list, the DNS query won`t be resolved and access will be denied. This access denial to harmful content saves the security team a lot of time and trouble. DNS filtering is a company`s first line of defense, as it can block harmful DNS connections on the spot.
4 Ways DNS Filtering Prevents Cyberattacks
DNS filtering blocks access to malicious websites, thus reducing the risk of infections. By doing this, it prevents:
- unsuspecting employees to fill in their credentials in spoofed login forms
- unintentional malware installation generated by clicking on a malicious link
- compromised machines beaconing to command-and-control servers
- data exfiltration to command-and-control servers
All these are possible due to the DNS filtering system’s ability to spot malicious domains. Some of the products out there use default operations for DNS content filtering while others are controlled by admins.
Here are three main filtering ways:
- category filters block access by evaluating the nature of the websites’ content: racial hatred, pornography, gambling, etc.
- keyword filters analyze a website`s content and decide to block it if they find certain words, like “chat” or “Netflix”, for example.
- finally, there are administrator-controlled Blacklists and Whitelists. Those offer personalized DNS content filtering, entirely decided by the administrator.
Not using a DNS filtering solution makes your company vulnerable to the following:
1. Step one: the user clicks on a malicious link, gets on a harmful website and downloads, without suspecting a thing, a malware installer.
2. Step two: the malware installer attempts (and succeeds) to connect with another harmful website, that deploys more malware that will compromise the system.
3. For the third step, the malware communicates to the C&C which starts exploiting the system for malicious purposes, like ransomware, for example.
Heimdal® DNS Security Solution
- Machine learning powered scans for all incoming online traffic;
- Stops data breaches before sensitive info can be exposed to the outside;
- Advanced DNS, HTTP and HTTPS filtering for all your endpoints;
- Protection against data leakage, APTs, ransomware and exploits;
How Can Heimdal®Help Enforce Strong DNS Security
DNS filtering is a great instrument; you should definitely insert it into your company`s security mix. However, most DNS security tools only rely on blocking threats that come from a list of known malicious domains.
So, what happens with the yet-undiscovered ones? As cyber criminals are currently able to use domain generation algorithms, they can instantly create hundreds of new malicious domains. So, it`s impossible to blocklist them all.
The good news is the DarkLayer Guard innovative DNS security solution, part of the Heimdal Threat Prevention product for endpoints and networks, does things differently and better. It uses our AI-driven ”Character Based” Neural networks intelligence to foresee threats that researchers did not discover yet. In doing so, it has a stunning 96% accuracy.
It also hunts, detects, and responds to threats faster than other DNS security solutions by using the Heimdal TTPC Technology. It prevents command & control server connections and data leakages and enables you to log network traffic.
All in all, DarkLayer Guard keeps your business safe from exploits, ransomware, and data leakage at a DNS level.
Wrapping Up
During this blog we kept highlighting how important DNS layer security is. Sure, you might not take our word for it. So here`s what the numbers say, according to the Global Cyber Alliance, about the economic impact of DNS filtering on the company`s finances.
Nearly 3,700 of the 11,079 breaches could have been avoided in the past five years, if a properly configurated DNS filtering solution had been in function. Consequently, losses between $19 and $37 billion in the U.S. or an average $150 to $200 billion globally could have been prevented.
In the end, using a professional DNS layer security solution to thoroughly protect the company`s assets will turn out to save a lot of money and energy for both the business and the team.
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