An exploit is a sequence of commands that takes advantage of a security vulnerability to gain unauthorized access to a system on your network. If successful, an Infection Monkey agent is released on the exploited system. The result of an attempted exploit is sent back to the Monkey Island as part of the telemetry.
If all you want to do is execute a shell command, configure the required commands in the Monkey Island's post-breach action (PBA) configuration section or [add a new PBA](../adding-post-breach-actions/).
However, if you have your eye on an interesting CVE that you would like the Infection Monkey to support, you must add a new exploit. Keep reading to learn how to add a new exploit.
The Infection Monkey exploiters are all built in a similar way. Each exploiter class inherits from the [`HostExploiter`](https://github.com/guardicore/monkey/blob/develop/monkey/infection_monkey/exploit/HostExploiter.py) class, which exposes two interface functions:
*`is_os_supported` - Returns a boolean value denoting whether the victim machine is supported by the exploiter (for example, returns `False` on Windows victim machines for the `SSHExploiter`). This can be used to thoroughly inspect a potential victim machine and decide whether to attempt the exploit on that particular machine (for example, by checking for open services matching specific versions).
In the [Infection Monkey's exploit directory](https://github.com/guardicore/monkey/tree/develop/monkey/infection_monkey/exploit), add the **exploit's logic** by defining a new class that inherits from [`HostExploiter`](https://github.com/guardicore/monkey/blob/develop/monkey/infection_monkey/exploit/HostExploiter.py). If your new exploit is a web RCE (remote code execution) exploit, inherit from [`WebRCE`](https://github.com/guardicore/monkey/blob/develop/monkey/infection_monkey/exploit/web_rce.py).
A good example of an exploiter class is the [`SSHExploiter`](https://github.com/guardicore/monkey/blob/develop/monkey/infection_monkey/exploit/sshexec.py). The [Log4Shell exploiter is a recently added web RCE exploit](https://github.com/guardicore/monkey/pull/1670) that is a good reference as well.
1. Add your **exploiter's description** to the [configuration schema](https://github.com/guardicore/monkey/blob/develop/monkey/monkey_island/cc/services/config_schema/definitions/exploiter_classes.py).
```py
...
{
"type": "string",
"enum": ["SmbExploiter"],
"title": "SMB Exploiter",
"safe": True,
"attack_techniques": ["T1110", "T1075", "T1035"],
"info": "Brute forces using credentials provided by user and hashes gathered by mimikatz.",
"info": "Information about your new exploiter.", <=================================
"link": "Link to the documentation page explaining your new exploiter.", <=================================
},
...
```
2. Update the default **list of exploiters** in the [configuration schema](https://github.com/guardicore/monkey/blob/develop/monkey/monkey_island/cc/services/config_schema/basic.py) by adding your new exploiter's class name.
1. In the [report generation pipeline](https://github.com/guardicore/monkey/blob/develop/monkey/monkey_island/cc/services/reporting/issue_processing/exploit_processing/exploiter_descriptor_enum.py), define how your **exploiter's data** should be processed and displayed in the report. Use the default `ExploitProcessor` or create a custom exploit processor if needed.
MYNEWEXPLOITER = ExploitDescriptor("MyNewExploiter", "My New Eexploiter", ExploitProcessor) <=================================
```
2. Describe how the Monkey Island should **display your exploiter's results** by defining the UI contents in the [security report](https://github.com/guardicore/monkey/blob/develop/monkey/monkey_island/cc/ui/src/components/report-components/SecurityReport.js).
### Documentation
**Update the documentation** to explain what your exploiter does in the [documentation framework](https://github.com/guardicore/monkey/blob/develop/docs/content/reference/exploiters/).