Direct Network Flood

What the technique is

Adversaries may attempt to cause a denial of service (DoS) by directly sending a high-volume of network traffic to a target. This DoS attack may also reduce the availability and functionality of the targeted system(s) and network. Direct Network Floods are when one or more systems are used to send a high-volume of network packets towards the targeted service's network. Almost any network protocol may be used for flooding. Stateless protocols such as UDP or ICMP are commonly used but stateful protocols such as TCP can be used as well. Botnets are commonly used to conduct network flooding attacks against networks and services. Large botnets can generate a significant amount of traffic from systems spread across the global Internet. Adversaries may have the resources to build out and control their own botnet infrastructure or may rent time on an existing botnet to conduct an attack. In some of the worst cases for distributed DoS (DDoS), so many systems are used to generate the flood that each one only needs to send out a small amount of traffic to produce enough volume to saturate the target network. In such circumstances, distinguishing DDoS traffic from legitimate clients becomes exceedingly difficult. Botnets have been used in some of the most high-profile DDoS flooding attacks, such as the 2012 series of incidents that targeted major US banks.

What MITRE says you would watch

• AN0969

  High-volume packet generation by local processes (e.g., PowerShell, cmd, curl.exe) or network service processes resulting in excessive outbound traffic over short time window, correlated with abnormal resource usage or degraded host responsiveness.

• AN0970

  Kernel or userland processes generating high-rate network traffic (ICMP, UDP, TCP SYN) beyond expected interface throughput or user behavior norms.

• AN0971

  Excessive outbound traffic via ping, curl, or custom scripts indicating flooding behavior, especially with no UI context or user interaction.