How To Implement a DNS Security Strategy

With very little discernment between enterprise-level organizations or SMBs and startups, the prevalence of cyberattacks across industries reveals that cybersecurity is a complex and ever evolving landscape difficult for even the best-trained IT professionals to keep pace with. As a network administrator or IT service provider looking to help small businesses secure their networks, it’s crucial that your approach to cybersecurity takes into account all attack surfaces a malicious threat actor might target.

Networks have several attack surfaces that can be extremely vulnerable if not properly maintained and configured. Perhaps one of the most vulnerable points of attack is when a user accesses a website or other online digital assets through a web browser, a process that involves a DNS. The domain name system (DNS) can be seen as one of the most vulnerable points of attack, and thus is the perfect starting point for IT professionals to work with small-business owners in securing their networks.

Domain Name System (DNS) acts as the directory for the internet, helping users connect with specific websites and experiences. This makes DNS security crucial in the modern digital landscape. As the mechanism for translating domain names into IP addresses, which in turn allows web browsers to load internet pages, the DNS layer is often targeted by sophisticated modern cyberattacks. 

DNS security encompasses the technical defense measures taken to protect DNS infrastructure, providing protection against the cyberattacks most often leveled at SMBs and startups, such as malware, ransomware, phishing attacks, and other scams that rely on users connecting to malicious websites.

DNS security is a conceptual approach to utilizing DNS-layer data gathered through various network monitoring tools to enhance the overall security of your organization’s network. There are multiple layers of security and best practices that should be implemented in order for DNS access to be properly secured.

Build your network with security in mind

At the highest level, DNS security is concerned with identifying whether a domain request is being made to a blacklisted DNS entry, and if so, blocks the user from accessing the website. This requires your team to program DNS-layer security to prevent users from connecting to rogue domains known for hosting malware and other malicious code.

Security protocol enforcement

One of the most important network security protocols that can be leveraged to protect your network at the DNS level is DNS Security Extensions (DNSSEC). Relying on digital signatures to secure and safeguard DNS records, DNSSEC is an additional layer of security designed to detect fraudulent and forged DNS entries. DNS digital signatures are attached to every step in the lookup process, and later verified with a mix of hashing and public key cryptography by the DNS resolver to verify DNS data.

Strictly enforced DNS logging protocols

As stated previously, DNS security is reliant upon your access to relevant and actionable data. DNS server management tools provide a number of configurable logging options that are flexible enough to allow network administrators to gather detailed DNS traffic activity. Administrators can adjust security levels in order to not only resolve DNS errors, but also to identify problems or mitigate the efforts of threat actors attacking the DNS infrastructure.

DNS security protocols are multifaceted, and neglect at any level can introduce risks that leave your network and data exposed to threat actors. 

Low availability and a lack of redundancy can impact business continuity

A properly configured network requires a designated DNS server, but DNS servers can be highly volatile and are often targeted in attacks. To ensure the security and stability of your network infrastructure, you should always have a backup DNS server in place in the event that your primary server is compromised.

Poor patching and updating practices damage network integrity

Your network is only as secure as the most vulnerable device attached to it. It’s extremely important in the modern digital landscape that network administrators and IT professionals work together to ensure all devices, and especially your DNS server software and DNS security management tools, are updated and patched as exploits come to light. 

While you might think this is a given, data in GetApp’s 2023 Data Security Survey revealed that nearly one in four (24%) IT security managers say unpatched applications are one of their company’s top security vulnerabilities.* 

Poorly configured networks leave your business vulnerable to attack

DNS security relies on network administrators adhering to best practices. We outlined the important role DNSSEC can play in network request authentication and ensuring the validity of sourced websites, but it’s not required that administrators include DNSSEC protocol. 

Additional problems can be introduced by corporate networks that allow DNS over HTTPS (DoH). While 80% of global internet traffic flows through HTTPS protocols, transmitting DNS queries across HTTPS can be problematic because the embedded encryption protocols prevent DNS security tools from properly tracking traffic. If you can’t avoid DoH, it’s necessary to fold Transport Layer Security/Secure Socket Layer (TLS/SSL) decryption into your repertoire to ensure TLS traffic can be made visible and malicious traffic identified. [1]

Without the right security protocols and third-party tools in place, the DNS layer is highly susceptible to specific types of attacks. While not exhaustive, this list provides insight into how malicious actors are targeting DNS servers in an attempt to bypass the security at this level.

• Spoofing or cache poisoning is an attack that alters DNS server data via forged DNS responses to redirect users to fake websites, where malware and other malicious code might then be uploaded.

• DNS tunneling attacks encapsulate malicious code within DNS queries and responses in order to circumvent firewalls and other security barriers.

• DNS hijacking, also referred to as DNS redirection, occurs when threat actors alter DNS settings so that legitimate queries are redirected to a malicious website.

• Distributed Denial-of-Service (DDoS) amplification attacks are DNS-focused methods of spoofing the source IP address of a DNS query and using it to then submit an exponentially large number of queries to the network’s dedicated DNS resolvers. This attack overwhelms the network with such a high volume of traffic that the DNS servers cannot respond to any queries and access is disrupted.

DNS security is one of the best early-stage methods of protecting and securing your organization’s network against cyberattacks. Aside from the best practices we’ve outlined to prevent attacks, there are other methods network administrators can use to strengthen the overall DNS security of a network.

1. Prioritize DDoS protection across multiple DNS security layers

Your DNS security system should come with layers of configurable protocols and monitoring tools specifically designed to mitigate against DDoS attacks. Your network administrators should have a clear view of traffic taking place across your network and be able to quickly identify and address malicious traffic or spikes in traffic. If your network is a potential target for high-volume attacks, your DDoS mitigation strategy should include the ability to defer and isolate traffic into a dedicated network designed to contain the traffic spike away from your standard network queries.

2. Isolate DNS servers through network segmentation

Modern networks are largely managed through third parties, allowing networks and DNS services to be highly scalable. However, shared public networks means that your organization’s network infrastructure can be impacted by attacks being made against other organizations’ DNS services. 

Ensure your DNS service provider takes a segmented approach to organizing their customers so you’re only sharing DNS server space with a limited number of potential targets, and in the event of an attack, they have the ability to provide mitigation solutions to each segment separately.

3. Do not use open source DNS resolvers

There are plenty of instances in marketing and business management where open source software solutions can be a boon to your team, offering highly configurable and stable solutions at little to no cost. 

However, when it comes to network management, open source resolvers can introduce exploits and vulnerabilities into your DNS layer that are difficult to identify or protect against. Relying on solutions that are not open source ensures you are using DNS-layer infrastructure that has been tested for vulnerabilities and is fully supported with patching and updates.

4. Make DNSSEC a mandatory inclusion in your DNS security

DNS servers are designed to respond to queries in the most efficient manner possible and often rely on cached data from DNS servers to provide the answers thought to be the best response to a given DNS query. Cache poisoning attacks are able to take advantage of this behavior because DNS servers don’t automatically verify the responses they receive or what happens to be in the query response. 

DNSSEC prevents these types of attacks by introducing cryptographic verification through public keys to validate that responses match the queries being made. Because all transactions across the DNS server and beyond are signed and verified, it becomes impossible for threat actors to spoof packets and redirect users to malware delivery sites.

5. Privatize your DNS network to increase resilience

A more expensive solution, you can pay your cloud-based service provider for access to a private DNS network, which minimizes your exposure to attacks focused on the vulnerabilities in public DNS servers. Private networks provide faster and more efficient connectivity and lower latency in the user experience, enhanced security due to the isolation of the network, and increased reliability due to segmentation and redundancy ensuring little to no downtime in the event of an attack.

6. Utilize an intelligent DNS management dashboard in network management

In order to secure business-critical network assets, it’s necessary to maintain your organization’s network so that it is both secure and compliant with evolving regulatory requirements. Network administrators need access to powerful security-focused software solutions in order to ensure 100% DNS server availability while tracking and mitigating security risks that could impact DNS stability.

Explore the GetApp directory of cybersecurity and network security-focused software solutions to give yourself the edge necessary to maintain and protect your digital infrastructure.

Small businesses and start-ups suffer from limited resources and budgets, and IT security is often deprioritized in favor of other business processes. This means when working to secure those systems, network administrators must prioritize their efforts around the most vulnerable avenues of attack. With SMBs increasingly being targeted in cyberattacks, the IT service providers and in-house IT professionals working to protect those companies’ networks have their work cut out for them.