DNS Calculation (T1568.003)

Tactic: Command and Control

Tactics: Command and Control
Platforms: ESXi, Linux, macOS, Windows
Reference: attack.mitre.org/techniques/T1568.003

Description

Adversaries may perform calculations on addresses returned in DNS results to determine which port and IP address to use for command and control, rather than relying on a predetermined port number or the actual returned IP address. A IP and/or port number calculation can be used to bypass egress filtering on a C2 channel.(Citation: Meyers Numbered Panda)

One implementation of DNS Calculation is to take the first three octets of an IP address in a DNS response and use those values to calculate the port for command and control traffic.(Citation: Meyers Numbered Panda)(Citation: Moran 2014)(Citation: Rapid7G20Espionage)

How GTK Cyber trains on this

GTK Cyber's Threat Hunting with Data Science course teaches you to build machine-learning detections for techniques like this across the MITRE ATT&CK framework, including the Command and Control tactic this technique falls under. Practitioner-led, focused on real detections, not memorizing technique IDs.

Threat Hunting with Data Science →·All training courses

Related techniques

Train your team to detect attacks like this.

GTK Cyber's Threat Hunting with Data Science course is taught by practitioners who detect this stuff for a living.

Explore Threat Hunting Training