Hello GionSix
Microsoft's Defender will find the KMS activater as a threat and other antivirus software will also do it.
We have no information if this kind of tools have malware, we simply advise not to use it.
If you do want to use illegal software please use it at your own risk.
I'm sorry that my answer is probably not what you are looking for but you are asking something we can not advise you on.
If you want to hang around the hacking/illegal software community then that is your choice.
Regards
Angelo