A while back I had a reservation with a hotel on Booking and I received a phish attempt that came directly via the Booking site domain email and also DMs but "sent" by the hotel. When I looked into it at the time, it seemed less like an issue of hotels specifically having their accounts infiltrated and more like some kind of message/email endpoint on Booking's end was being abused in a similar manner.
I'm not sure this is the same type of issue but found this interesting, especially since apparently it's been reported to MS and no action has been taken.
I'm not sure this is the same type of issue but found this interesting, especially since apparently it's been reported to MS and no action has been taken.