Building Payloads

Here we can see that the operator selects the different payload options they desire in the web user interface and clicks submit. That information goes to Mythic which looks up all the database objects corresponding to the user's selection. Mythic then registers a payload in a building state. Mythic sends all this information to the corresponding Payload Type container to build an agent to meet the desired specifications. The corresponding build command parses these parameters, stamps in any required user parameters (such as callback host, port, jitter, etc) and uses any user supplied build parameters (such as exe/dll/raw) to build the agent.

In the build process, there's a lot of room for customizing. Since it's all async through rabbitMQ, you are free to stamp code together, spin off subprocesses (like mono or go) to build your agent, or even make web requests to CI/CD pipelines to build the agent for you. Eventually, this process either returns an agent or some sort of error. That final result gets send back to Mythic via rabbitMQ which then updates the database and user interface to allow an operator to download their payload.

Translation Container Version

How does this process work if there's a translation container involved though?

Notice how the only real difference here is that IF the payload type definition says for MythicEncrypts=False and there's a translation container, then it's up to the translation container to generate any encryption keys. These keys can be part of a C2 Profile or they could be part of a payload type's build parameters. This is why you see this flow happening in two places. Other than that, when it comes to building a payload, the translation container has very little interaction.