The main purpose of this malware is to organize DDoS attacks on demand. Several types of attacking techniques are supported, including the following:
- UDP flood
- SYN flood
- ACK flood
- GRE flood
- HTTP flood
- DNS flood
Here is the snippet of Mirai's source code mentioning them:
Figure 9: Different attack vectors of Mirai malware
As we can see here, the authors implemented multiple options so that they could select the most efficient attack against a particular victim.