- Tactics
- Command and Control
- Platforms
- Linux, macOS, Windows, ESXi
- Reference
- attack.mitre.org/techniques/T1568.001
Description
Adversaries may use Fast Flux DNS to hide a command and control channel behind an array of rapidly changing IP addresses linked to a single domain resolution. This technique uses a fully qualified domain name, with multiple IP addresses assigned to it which are swapped with high frequency, using a combination of round robin IP addressing and short Time-To-Live (TTL) for a DNS resource record.(Citation: MehtaFastFluxPt1)(Citation: MehtaFastFluxPt2)(Citation: Fast Flux - Welivesecurity)
The simplest, “single-flux” method, involves registering and de-registering an addresses as part of the DNS A (address) record list for a single DNS name. These registrations have a five-minute average lifespan, resulting in a constant shuffle of IP address resolution.(Citation: Fast Flux - Welivesecurity)
In contrast, the “double-flux” method registers and de-registers an address as part of the DNS Name Server record list for the DNS zone, providing additional resilience for the connection. With double-flux additional hosts can act as a proxy to the C2 host, further insulating the true source of the C2 channel.
How GTK Cyber trains on this
GTK Cyber's hands-on training programs cover detection engineering across the MITRE ATT&CK framework, including the Command and Control tactic this technique falls under. Our practitioner-led courses focus on building real detections, not just memorizing technique IDs.
Related techniques
- T1001 — Data Obfuscation
- T1008 — Fallback Channels
- T1071 — Application Layer Protocol
- T1090 — Proxy
- T1092 — Communication Through Removable Media
- T1095 — Non-Application Layer Protocol
- T1102 — Web Service
- T1104 — Multi-Stage Channels
- T1105 — Ingress Tool Transfer
- T1132 — Data Encoding
- T1205 — Traffic Signaling
- T1219 — Remote Access Tools