Introduction

The Domain Name System (DNS) is like the phonebook of the internet, translating domain names into IP addresses. Cybercriminals often rely on DNS to hide activity, launch phishing attacks, or spread malware. DNS forensics allows investigators to trace and analyze these activities.

🖥️ What Are DNS Logs?

• DNS logs record every DNS query and response for a network.

• They include information like:

  • Query time and date

  • Requested domain name

  • IP addresses of the requester

  • Response codes

These logs provide a timeline of web activity that can help investigators reconstruct attacks or trace malicious actors.

🕵️‍♂️ How Investigators Use DNS Logs

1. Identifying Malicious Domains:

   • Detect connections to phishing sites or malware command-and-control servers.

2. Tracing Threat Actors:

   • DNS queries can reveal the source of the request, even when proxies are used.

3. Reconstructing Attack Timelines:

   • Investigators can track when a device contacted a suspicious domain to understand the sequence of attacks.

4. Correlating Data Across Networks:

   • Cross-referencing DNS logs from multiple sources can reveal patterns or clusters of malicious activity.

🔗 Tools for DNS Forensics

• Wireshark: Capture and analyze DNS traffic.

• Splunk: Aggregate and visualize DNS log data.

• Security Onion: Open-source platform for network monitoring, including DNS.

• Passive DNS Databases: Historical DNS data to trace previously used domains.

✅ Best Practices

1. Always store DNS logs securely for forensic purposes.

2. Correlate DNS data with firewall, proxy, and endpoint logs for a complete picture.

3. Monitor for unusual DNS traffic patterns, which often indicate attacks.

4. Respect privacy laws and regulations when analyzing DNS data.