The Domain Name System (DNS) is often described as the phonebook of the Internet because it translates domain names into IP addresses. Every time a user visits a website, opens a cloud application, or downloads software, DNS is usually involved. Because DNS traffic is generated constantly across enterprise environments, it is easy to overlook. However, attackers also rely on DNS during many stages of a cyberattack, making DNS monitoring an essential responsibility for Security Operations Center (SOC) analysts.
By understanding how DNS works and how attackers abuse it, analysts can improve threat detection and incident response. The MITRE ATT&CK framework and the NIST Cybersecurity Framework (CSF) both emphasize the importance of monitoring network activity and identifying abnormal behavior across enterprise environments.
Why DNS Is Important
DNS allows devices to locate services by converting human-readable domain names into IP addresses. Without DNS, users would need to remember numerical IP addresses instead of website names.
Since nearly every network connection begins with a DNS request, DNS logs provide valuable information about user activity, applications, and potential security threats.
For SOC analysts, DNS logs can answer important questions such as:
- Which domains did a system contact?
- When did the communication occur?
- Which device initiated the request?
- Are multiple systems contacting the same suspicious domain?
Because DNS activity often occurs before network communication is established, it can provide one of the earliest indicators of malicious behavior.
DNS and MITRE ATT&CK
The MITRE ATT&CK framework documents several techniques that involve DNS.
Attackers frequently use DNS before communicating with Command and Control (C2) infrastructure. A compromised endpoint may perform DNS lookups for attacker-controlled domains before establishing outbound connections.
DNS activity may also help analysts identify malware attempting to download additional payloads or communicate with remote servers.
Although a single DNS request rarely proves malicious activity, repeated queries to newly registered, uncommon, or suspicious domains may justify further investigation.
MITRE ATT&CK encourages analysts to correlate DNS activity with endpoint, authentication, and network telemetry rather than investigating DNS logs independently.
NIST Recommendations
The NIST Cybersecurity Framework emphasizes continuous monitoring and centralized logging to improve organizational visibility.
DNS logs should be collected alongside firewall logs, endpoint telemetry, authentication records, and proxy logs whenever possible. Centralizing these data sources allows analysts to reconstruct attack timelines more accurately.
Organizations should also establish normal DNS baselines. Internal applications, cloud services, and operating system updates all generate legitimate DNS traffic. Understanding these normal patterns helps analysts identify anomalies that may indicate malicious activity.
Continuous monitoring allows security teams to detect suspicious communication before attackers achieve their objectives.
Investigation Tips for SOC Analysts
When reviewing DNS activity, analysts should avoid assuming that every unfamiliar domain is malicious.
Instead, ask questions such as:
- Is the domain known or newly registered?
- Has this endpoint contacted the domain previously?
- Are multiple devices communicating with the same domain?
- Was PowerShell, a web browser, or another application responsible for the request?
- Did suspicious process execution or authentication events occur around the same time?
Correlating DNS logs with process creation events, firewall activity, and endpoint telemetry provides valuable context during an investigation and significantly improves detection accuracy.
Conclusion
DNS is one of the most frequently used services within enterprise networks, making it an excellent source of security intelligence. Because attackers also rely on DNS to locate command-and-control servers and external resources, monitoring DNS activity is a critical part of effective threat detection.
By combining DNS analysis with the behavioral guidance of the MITRE ATT&CK framework and the continuous monitoring principles of the NIST Cybersecurity Framework, SOC analysts can identify suspicious activity earlier and conduct more comprehensive investigations. Understanding DNS is not just a networking skill—it is an essential capability for modern cybersecurity professionals.