about Apple calendar (including iPhone and Mac) is easy to be infected with viruses

I am a long-time Apple fan. Although all Apple products are very good and safe. However, the Apple calendar (including iPhone and Mac) is easy to be infected with viruses. There are many web advertisements, pornographic links, and viral plug-ins that pretend to be my calendar arrangements. The content of this calendar reminder cannot be deleted or changed. . Because Apple calendar is bound to iCloud, those viruses still appear when deleted and reinstalled. Although these viruses cannot damage the system, they completely paralyze Calendar. In order to get rid of these viruses, I can only delete Calendar and use Google Calendar. I hope Apple employees pay attention to Calendar and find a solution. Let me use Apple calendar again.

Thank you