The internet has fueled growth opportunities for enterprises by allowing them to establish an online presence, communicate with customers, process transactions and provide support, among other benefits. But it’s a double-edged sword: A cyberattack that compromises these business advantages can easily result in significant losses of money, customers, credibility and reputation, and increases the risk of completely going out of business. That’s why it’s critical to have a cybersecurity strategy in place to protect your enterprise from attackers that exploit internet vulnerabilities.
How DNS Analytics Can Boost Your Defense
The Domain Name System (DNS) is one of the foundational components of the internet that malicious actors commonly exploit and use to deploy and control their attack framework. The internet relies on this system to translate domain names into numbers, known as Internet Protocol (IP) addresses. Giving each IP a unique identifier allows computers and devices to send and receive information across networks. However, DNS also opens the door for opportunistic cyberattackers to infiltrate networks and access sensitive information.
Here are five tips to help you uncover hidden cyberthreats and protect your enterprise with DNS analytics.
1. Think Like an Attacker to Defend Your Enterprise
To protect the key assets of your enterprise and allocate sufficient resources to defend them, you must understand why a threat actor would be interested in attacking your organization. Attacker motivations can vary depending on the industry and geography of your enterprise, but the typical drivers are political and ideological differences, fame and recognition, and the opportunity to make money.
When it comes to DNS, bad actors have a vast arsenal of weapons they can utilize. Some of the most common methods of attack to anticipate are distributed denial-of-service (DDoS) attacks, DNS data exfiltration, cache poisoning and fast fluxing. As enterprises increase their security spending, cyberattacks become more innovative and sophisticated, including novel ways to abuse the DNS protocol. Malware continues to be the preferred method of threat actors, and domain generation algorithms (DGAs) are still widely used, but even that method has evolved to avoid detection.
2. Make DNS Monitoring a Habit
Passive DNS data is important because it is unlikely that a new network connection doesn’t have an associated DNS lookup. It also means that if you collect DNS data correctly, you can see most of the network activity in your environment. A more interesting subject is what we can do with this data to create more local security insights. Even though it is not hard to bypass DNS lookup, such network connections are suspicious and easy to detect.
3. Understand Communication and Traffic Patterns
Attackers leverage the DNS protocol in various ways — some of which are way ahead of our detection tools — however, there are always anomalies that we can observe in the DNS request sent out by endpoints. DNS traffic patterns vary by enterprise, so understanding what the normal pattern for your organization is will enable you to spot pattern anomalies easily.
A robust, secure system should be able to detect exfiltration via DNS tunneling software, which is not as easy as it sounds due to their different communication patterns. DNS tunneling software communication is reliable and frequent, the flow is bidirectional, and it is typically long. On the other hand, DNS exfiltration communication is opportunistic and unexpected, and possibly unidirectional since attackers are looking for the right moment to sneak out valuable data.
4. Get the Right Tools in Place
When analyzing which tools are the best to protect your organization against attacks leveraging DNS, consider what assets you want to protect and the outcomes you would like your analysts to achieve. There are many tools that can be pieced together to create a solution depending on your goals, such as firewalls, traffic analyzers and intrusion detection systems (IDSs).
To enhance the day-to-day activities of your security operations center (SOC), enable your team to conduct comprehensive analysis on domain activity and assign an appropriate risk rating, your SOC analysts should take advantage of threat intelligence feeds. These feeds empower analysts to understand the tactics, techniques and procedures (TTPs) of attackers and provide them with a list of malicious domains to block or alert on their security system. When this information is correlated with internal enterprise information through a security information and event management (SIEM) platform, analysts have full visibility to detect or anticipate ongoing attacks.
5. Be Proactive and Go Threat Hunting
Technology is a very useful tool that allows us to automate processes and alerts us of suspicious activity within our networks — but it is not perfect. Threat hunting can complement and strengthen your defense strategy by proactively searching for indicators of compromise (IoC) that traditional detection tools might miss. To succeed at threat hunting, you must define a baseline within your environment and then define the anomalies that you are going to look for.
A standard method for threat hunting is searching for unusual and unknown DNS requests, which can catch intruders that have already infiltrated your system as well as would-be intruders. Some indicators of abnormal DNS requests include the number of NXDOMAIN records received by an endpoint, the number of queries an endpoint sends out and new query patterns. If you identify a potential threat, an incident response (IR) team can help resolve and remediate the situation by analyzing the data.
Every organization is unique, but by understanding the basics of DNS analytics, the common methods of attack and the tools available to security teams, you will be better prepared to protect your enterprise from hidden cyberthreats.
We invite you to check out our on-demand webinar to learn even more about DNS threat hunting.