I'm using Google Calendar on a daily basis and today, when I opened it to add another reminder, I immediately discovered the anomaly(who wouldn't):
"Your iphoneX is ready for PickUp".
Because a couple of hours ago I got a Gmail prompt to confirm a Log In from a different country(which I denied), it's clear that I've been under a small attack.
This is generally possible because Google Calendar allows events to be added to your calendar in certain circumstances. For instance, when you get a flight confirmation into your email, based on it a respective event is going to be added to your calendar.
In this case, the spammers will just add your email as an invitee and boom, it's automatically added to your calendar without even accepting it, kind of creepy, no?
To stop adding calendar invites automatically
- Find the gear icon and click "Settings" from the drop-down menu.
- Choose "Event Settings" from the left sidebar and choose "No, only show invitations to which I have responded" for the "Automatically add invitations"
Keep in mind that by doing this you're not going to get any events added to your calendar automatically from your Gmail account, so it's your choice.
Hopefully, Google finds a way around it soon.