First Steps

What are the first things to do when creating a new payload type in Mythic?

So you want to make a new Payload Type

The first step is to copy the /Mythic/Example_Payload_Type folder into the /Mythic/Payload_Types/ folder and rename it to match the name of your new agent. For the purposes here, let's assume your new agent is called MyNewAgent. So you'd copy that directory as /Mythic/Payload_Types/MyNewAgent.

The next thing you need to do is edit the builder file (https://github.com/its-a-feature/Mythic/blob/master/Example_Payload_Type/mythic/agent_functions/builder.py) to reflect the information for your new agent. Specifically, you'll want to edit it like:

from mythic_payloadtype_container.MythicCommandBase import *
from mythic_payloadtype_container.PayloadBuilder import *
import asyncio
import os
from distutils.dir_util import copy_tree
import tempfile

# define your payload type class here, it must extend the PayloadType class though
class MyNewAgent(PayloadType):

    name = "MyNewAgent"  # name that would show up in the UI
    file_extension = "exe"  # default file extension to use when creating payloads
    author = "@YourHandleHere"  # author of the payload type
    supported_os = [  # supported OS and architecture combos
        SupportedOS.Windows, SupportedOS.Linux # update this list with all the OSes your agent supports
    ]
    wrapper = False  # does this payload type act as a wrapper for another payloads inside of it?
    # if the payload supports any wrapper payloads, list those here
    wrapped_payloads = [] # ex: "service_wrapper"
    note = "Any note you want to show up about your payload type in the UI"
    supports_dynamic_loading = False  # setting this to True allows users to only select a subset of commands when generating a payload
    build_parameters = {
        #  these are all the build parameters that will be presented to the user when creating your payload
        # we'll leave this blank for now
    }
    #  the names of the c2 profiles that your agent supports
    c2_profiles = ["http"]
    # after your class has been instantiated by the mythic_service in this docker container and all required build parameters have values
    # then this function is called to actually build the payload
    async def build(self) -> BuildResponse:
        # this function gets called to create an instance of your payload
        resp = BuildResponse(status=BuildStatus.Error)
        return resp

More information on each component in the file can be found in Payload Type Info. Now you can run sudo ./mythic-cli payload add MyNewAgent and sudo ./mythic-cli payload start MyNewAgent and you'll see the container build, start, and you'll see it sync with the Mythic server (more about that process at Container Syncing).

Congratulations! You now have a payload type that Mythic recognizes!

Now you'll want to actually configure your Docker Container, look into building your agent, how to declare new commands, how to process tasking to these commands, and finally hooking your agent into all the cool features of Mythic.