@keisuke it's not really something you have to worry about if you're on a single user instance or even a small one with locked registration. this is the case of an unknown user uploading a malicious file.

someone can correct me if i'm wrong, but i'm pretty sure this couldn't happen to gameliberty either because you can't upload JS files to begin with. it's a bad idea in general to let random users upload files that can contain executable code unless your security is airtight, not from a hobbyist. a social media site should probably only allow videos and photos (which can come with their own problems but still much safer than this).