Every time you visit a website, send an email, or use an online service, DNS traffic is quietly working in the background. It’s the behind-the-scenes exchange of messages that turns a domain name like example.com into the numerical IP address your device needs to connect.

 

While most DNS traffic is harmless and essential, attackers often exploit it to hide malicious activities, steal data, or control compromised systems. That’s why understanding DNS traffic isn’t just for network engineers; it’s essential for anyone serious about cyber security.

 

Let’s learn what DNS traffic is and why it matters for network security.

 

What is DNS traffic?

 

DNS (Domain Name System) traffic refers to the data exchanged between a client (like your computer or phone) and a DNS server to translate human-readable domain names into machine-readable IP addresses. 

 

Without DNS, the internet would not be user-friendly; you’d have to remember strings of numbers instead of “example.com.”

 

How DNS traffic works

 

Here’s the step-by-step journey of DNS traffic:

 

1. You type a domain name into your browser.
2. Your device sends a DNS query asking for the IP address linked to that domain.
3. A DNS server receives the query and checks its records or asks other DNS servers if it doesn’t know the answer.
4. The DNS server sends back a DNS response with the IP address.
5. Your device connects to the website or service using that IP address.

 

Example: You enter www.cyberarrow.io → your browser sends a DNS query → the DNS server replies with the site’s IP → your device connects.

 

Types of DNS traffic

 

There are two types of DNS traffic: 

 

Legitimate DNS traffic

 

These are normal queries and responses for browsing, emails, and apps.

Examples: visiting a website, using a mobile app that loads content, sending an email.

 

Malicious DNS traffic

 

Traffic intentionally generated by attackers.

 

Often used to:

 

• Steal data using DNS tunneling.
• Redirect users to fake websites.
• Allow malware to communicate with command-and-control servers.

 

Legitimate traffic follows predictable patterns, while malicious DNS traffic often appears unusual, frequent, or directed to suspicious domains.

 

 

Why DNS traffic matters for security

 

While DNS is essential for internet functionality, it’s also a common vector for cyberattacks. 

 

Attackers can abuse DNS traffic for:

 

• Data exfiltration: Using DNS queries to secretly transfer stolen data.
• DNS tunneling: Hiding malicious traffic inside DNS queries.
  Phishing & malware delivery: Redirecting users to malicious domains.
• DDoS amplification: Overloading servers with DNS requests.

 

Because most organizations allow DNS traffic by default, malicious use can go unnoticed without proper monitoring.

 

Common DNS traffic threats

 

These include the following: 

 

• DNS hijacking: Attackers change DNS settings to redirect traffic to malicious sites. For instance, a corporate DNS record is modified to send users to a fake login page that steals credentials.

 

• DNS amplification attacks: Exploiting open DNS resolvers to flood a target with massive traffic. For example, an attacker sends small requests to misconfigured DNS servers, which respond with large payloads to the victim.

 

• DNS tunneling: Embedding data inside DNS requests for covert communication. For example, malware on a compromised device sends stolen files to an attacker using DNS queries.

 

• DNS spoofing: DNS spoofing is the injection of false DNS records into the cache so users are redirected to malicious sites. For example, a user types in “mybank.com” but is sent to a fake banking site that looks identical.

 

Best practices for securing DNS traffic

 

Here is a list of best practices you can follow to secure your DNS traffic:

 

1. Use DNSSEC to validate DNS responses

 

DNS Security Extensions (DNSSEC) protect your DNS traffic by adding cryptographic signatures to DNS data. This means when your device receives a DNS response, it can verify that the information hasn’t been altered or spoofed. Enabling DNSSEC helps prevent attacks like DNS spoofing and cache poisoning that redirect users to malicious sites.

 

Quick link: Spoofing vs phishing

 

2. Encrypt DNS queries with DoH or DoT

 

DNS queries sent in plain text are vulnerable to interception and manipulation. Encrypting DNS traffic using DNS over HTTPS (DoH) or DNS over TLS (DoT) ensures the queries and responses are secure and private. This encryption makes it much harder for attackers to eavesdrop on or tamper with DNS requests as they travel between your devices and DNS servers.

 

3. Choose trusted and secure DNS resolvers

 

Using well-known DNS resolvers from providers like Cloudflare, Google, or Quad9 adds an extra layer of security. These services maintain updated threat intelligence and can block requests to dangerous or suspicious domains automatically. Switching your network or devices to these resolvers helps reduce the chance of connecting to phishing or malware sites.

 

4. Monitor DNS traffic for anomalies

 

Actively monitoring DNS queries allows you to spot unusual patterns, such as repeated requests to rare domains or unexpected spikes in DNS traffic. These anomalies often signal malicious activity, like data exfiltration through DNS tunneling or communication with command-and-control servers. Keeping DNS logs and analyzing them regularly is vital for early threat detection.

 

5. Control and restrict DNS traffic

 

Limiting DNS queries to authorized devices and resolvers reduces risk. By enforcing network policies or firewall rules that only allow DNS traffic to approved servers, you prevent unauthorized or compromised devices from using rogue DNS services. This helps stop attackers from redirecting traffic or bypassing security controls through malicious DNS servers.

 

Example: DNS traffic in incident response

 

When responding to a potential security incident, analyzing DNS traffic can reveal:

 

• The domains accessed before and after the compromise.
• Potential command-and-control servers communicating with infected devices.
• Exfiltration methods used by attackers.

 

For instance, during a ransomware investigation, DNS logs revealed communication between the infected host and a domain associated with known ransomware groups, allowing security teams to block further contact.

 

Empower your workforce and protect your network with the CyberArrow Awareness Platform

 

Securing DNS traffic relies on both technology and well-informed users. CyberArrow Awareness Platform helps your organization by:

 

• Training employees to identify phishing, social engineering, and DNS-based threats.
• Offering tailored learning paths to keep security knowledge up to date.
• Supporting compliance with security policies and frameworks.

 

By combining education with active monitoring, CyberArrow helps reduce the risk of DNS-related attacks and strengthens your overall security and compliance posture.

 

See how the CyberArrow Awareness Platform increased security awareness among Silal’s employees.