How does DNS Tunneling exfiltrate data?

DNS tunneling is a technique that exploits the DNS protocol to tunnel malware and other data through a client-server model. DNS tunneling can be used for data exfiltration, command and control, or IP-over-DNS tunneling. DNS tunneling works by encoding the information of other protocols or programs in DNS queries and responses. An attacker registers a domain, such as badsite.com, and sets up a malicious DNS server that can interpret the encoded data. The attacker then infects a client with malware that can send and receive DNS queries to the attacker’s domain. The malware can use DNS queries to request commands from the attacker, or to send sensitive data to the attacker. The DNS queries and responses look like normal DNS traffic, but they contain hidden data that can bypass network defenses123. References := 1: What Is DNS Tunneling? - Palo Alto Networks 2: What is DNS Tunneling? - Check Point Software 3: What Is DNS Tunneling and How to Detect and Prevent Attacks