The Importance of DNS Security in the AI-Driven Digital Age

DNS Security safeguards the internet’s phone book against cyberattacks. This blog shares real-life examples of DNS vulnerabilities and provides best practices to ensure robust protection against today’s sophisticated cyber threats.

In today’s ever-evolving cybersecurity landscape, where threats are growing more sophisticated by the day, the promise of AI in bolstering cyber defenses is undeniable. However, to truly capitalize on AI’s potential, solid security foundations – such as DNS Security – must first be established. In this blog, we will take a look at a core technology of the Internet – DNS or Domain Name System – that acts as the Internet’s “phone book,” and explore why investing in DNS can provide far more value than just focusing on the new tools of cybersecurity.

High DNS Exposure in a Threatening Environment

It is a fact that cyberattacks are only going to increase in both frequency and their negative impact on business. Consequently, it should come as no surprise that senior executives and board members everywhere are starting to demand visibility of cyber risks on their dashboards. No business wants to become the next to fall from grace.

As an example, Equifax’s former CEO, Richard Smith, knows only too well the consequences of not prioritizing cyber risk. He was dragged in front of the US Digital Commerce and Consumer Protection Subcommittee on Capitol Hill to explain how cyber criminals managed to steal over 143 million records of personal information.

The integration of Artificial Intelligence, Machine Learning, and other advanced technologies in cybersecurity represents a significant leap forward in the fight against cyber threats. These technologies can offer powerful tools for threat detection, response, and prevention, enabling organizations to protect their digital assets more effectively.

However, the large array of solutions that promise to mitigate cyberthreats can often confuse even the sharpest of buyers. Buzzwords like next-generation, Machine Learning, Artificial Intelligence (even Quantum computing) tend to take the focus away from the fundamentals. But, before implementing even more cybersecurity solutions, it is important to go back to basics, look at the technology at the heart of the Internet such as the Domain Name System (DNS) protocol, and explore the value of investing in its protection. 

Understanding DNS

In the vast landscape of the Internet, the DNS serves as the crucial directory that translates human-readable domain names into IP addresses. Often likened to the internet’s phone book, DNS enables users to access websites and services easily. However, its critical role in internet functionality also makes it a prime target for cyberattacks. Understanding DNS Security and the types of cyber threats that exploit it is essential for maintaining a safe and reliable online environment.

DNS operates by mapping domain names (like www.efficientip.com) to their respective IP addresses (such as 192.0.2.1). This process involves several steps and components, including DNS caching, DNS resolvers, root, TLD, and authoritative name servers. In a nutshell, when you type a URL into your browser, the recursive DNS resolver first queries the root name server if the data is not in the DNS cache, and then routes to the various DNS servers listed above to find the corresponding IP address, enabling your browser to load the website.

To understand how unprotected DNS can highly damage organizations, even those protected with antivirus, Next-Gen Firewalls, or more sophisticated AI tools as discussed above, let’s take an example of a recent DNS attack.

Ukraine’s electricity grid was attacked when winter was at its peak, in December. It is still considered as one of the most advanced and complex attacks as it caused systems to be inoperable. It used spear phishing to spread malware.

For cybercriminals to succeed in this attack, the following had to happen: 

An employee had to open a phishing email. The criminals scoped out the employees on social media and other platforms before sending them the emails. The target victims had to willingly open Microsoft Word documents with infected Macros.

The malicious malware had to call back home for “instructions” and this call back required DNS.

DNS is simply a crucial technology that glues together the whole of cyberspace. Every bit of other technologies out there, including smartphones, tablets, smart watches, smart cars, webcams, smart TVs and more, wholly rely on DNS to function.

Common DNS-Based Cyber Attacks

At its core, DNS is designed for efficiency and reliability, but not inherently for security. This lack of built-in security makes it susceptible to various types of cyberattacks. DNS is therefore used as both the target of attacks and as an attack vector. It is worth remembering that 85% of malware uses DNS. Some of the most common DNS-related attacks include:

1. DNS Spoofing (Cache Poisoning)

DNS spoofing, or cache poisoning, involves corrupting the DNS cache with false information. Attackers manipulate the DNS responses to direct users to malicious sites instead of legitimate ones. For instance, a user attempting to visit their bank’s website might be redirected to a fraudulent site designed to steal login credentials. This type of attack can lead to significant data breaches and financial losses.

2. DNS Amplification Attacks

DNS amplification attacks are a form of Distributed Denial of Service (DDoS) attack. In these attacks, cybercriminals exploit DNS servers to flood a target with a massive amount of traffic, overwhelming the system and causing it to crash. The attacker sends a small DNS query with a spoofed IP address (the target’s IP), and the DNS server responds with a much larger reply to the target, amplifying the traffic volume. These attacks are among the most common types of DDoS attacks used by cybercriminals to disrupt online services and networks.

3. DNS Tunneling

DNS tunneling involves encoding data from other protocols within DNS queries and responses. Attackers can use this method for DNS data exfiltration or to establish command-and-control channels for malware and ransomware. Because DNS traffic is often allowed through firewalls and security filters, this technique can bypass traditional enterprise network security measures.

4. Domain Hijacking

Domain hijacking occurs when attackers gain unauthorized access to the domain registration account, allowing them to alter DNS settings. By changing the DNS records, attackers can redirect traffic intended for the legitimate site to malicious servers. This can lead to phishing attacks, data theft, and significant reputational damage.

As we can see from the above examples, DNS attacks can cause significant damage to organizations and individuals by disrupting internet services, compromising security, and impacting data integrity and confidentiality.

DNS Attacks Real Life Examples

Large Telcos are often targeted and need to sustain a high load of attacks

In the Telco sector, cyber attacks using DNS have been a significant concern due to the critical role DNS plays in network connectivity and operations. A notable example involves a Turkish ISP facing a major challenge with a number of cybercriminals using DNS cache poisoning to redirect their subscribers to malicious websites. These sites then delivered malware or phishing content to the users. The volume of DNS cache poisoning attacks was so high that DNS cache performances were going down and DNS was eventually crashing. This ISP was well protected with load balancers, Next-Gen Firewalls, and other sophisticated tools, but their DNS was not able to sustain the massive traffic load of so many attacks.  Once they understood that rather than trying to prevent attacks —a virtually impossible task—a better strategy was to simply protect the DNS cache whilst under attacks to continue serving DNS queries to their customers, they solved the problem. 

And sometimes things are even worse than you imagined, in the case of live deployment on the fly due to an attack. In this situation, speed, expertise, and the right solution are key.

For another Telco DDI project deployment in Africa, the appliances had been installed and configuration was underway, with testing and validation set to begin,  when the Telco encountered serious disruptions on their network infrastructure. Worms and malware were spreading rapidly, requiring an immediate response. The Network Manager asked  to put in production the DNS Security solution and configure countermeasures on the fly. While skipping testing is not recommended as a best practice, the positive impact of the protective DNS with robust security measures was quickly evident. All new attacks were put in quarantine, while the ISP’s network team was able to identify the IP source of attackers and work on restoring their services. This experience demonstrated in “real life” how robust and well-protected DNS, thanks to a solution such as EfficientIP’s DNS Security solution can be instrumental in safeguarding networks, mitigating impact such as exfiltrated data, and ensuring service continuity.

Best Practices for DNS Security

We have seen that cybercriminals abuse DNS in many ways, such as: 

• Create fake domains for commercial fraud or using Domain Generated Algorithms (DGAs) to frequently change the domains used to carry out advanced attacks, including malware.
• Automatically hijack internet browsing traffic to a website and serve a malicious but similar-looking website page.
• Launch Denial of Service (DoS) attacks, causing a website to become unavailable.
• Stealthily engage in data theft using DNS technology.

Put another way, if criminals rely on DNS to succeed, the converse must be true too. A well-configured and secured DNS is an effective and robust first line of defense solution to protect data and users, quickly detect malicious DNS activities, and respond to various types of cyber attacks, with the objective to maintain service continuity.

A protected DNS serves as an early and reliable indicator of malicious activity from inside or outside of your organization. Furthermore, it can be used to stop this activity at an early stage.

Therefore, robust DNS Security measures are essential. Here are several strategies to enhance DNS Security and implement protective DNS for cyber resilience:

1. Implementing Secure DNS Configurations:

DNS server configuration needs to follow specific rules for optimal security. This includes hardening DNS servers, restricting access to authoritative DNS servers, using Access Control Lists (ACLs), and implementing Response Rate Limiting (RRL) to thwart DNS amplification attacks.

2. Implementing DNS Filtering:

DNS filtering can block access to known malicious domains. This involves using DNS threat intelligence to maintain a list of malicious sites and prevent users from accessing them by blocking or quarantining them, thereby mitigating phishing and malware distribution risks. Advanced and granular DNS filtering further enhances DNS protection by implementing richer and more modular security policies that contribute to micro-segmentation, a key component of a Zero Trust architecture.

3. Regularly Updating DNS Software:

Keeping DNS software up to date with the latest patches and security updates is crucial. Vulnerabilities in outdated software can be exploited by attackers to gain control of DNS servers.

4. Using Redundant DNS Servers:

Employing multiple DNS servers in different geographical locations ensures that if one server is compromised or goes offline, others can continue to provide DNS resolution. This enhances the resilience and availability of DNS services. Having a hybrid DNS solution which can carry multiple DNS engines, switching from one to another, is another protective DNS capability which can solve issues when one DNS engine is at risk.

5. Monitoring and Logging DNS Traffic:

Providing unified visibility on your entire network traffic through DNS is essential. Continuous monitoring, logging of DNS traffic, and DNS insights and metrics on DNS health, contributes to the Network Source of Truth (NSoT) and DDI observability and helps detect and investigate abnormal patterns that may indicate an ongoing attack. This proactive approach allows for timely intervention and mitigation of potential cyberthreats. 

Following these best practices will simplify and increase the operational efficiency of security, SecOps, and NetSecOps teams in their daily activities.

Looking forward

DNS Security is not just a technical necessity; it is a critical component of overall cybersecurity strategy. As the backbone of internet communication, DNS must be fortified against an evolving landscape of cyber threats. By understanding the vulnerabilities and implementing robust security measures and protective DNS, organizations can effectively protect, detect, and respond to potential cyberthreats, ensuring the safety of their digital assets and maintaining the trust of their users. In an era where cyberattacks are increasingly sophisticated and frequent, prioritizing DNS Security is paramount to safeguarding the integrity and reliability of the internet. Learn more about DNS Security best practices in our white paper.