Cyber criminals exploited the royal baby's birth by sending out a mass of fake links to a live blogging site in a bid to steals bank details, web security experts said.
Fraudsters are believed to have targeted tens of millions of people just hours after the Duke and Duchess of Cambridge introduced their new son to the world.
Analysts said the group launched its “malicious email campaign” yesterday evening and targeted subscribers to the ScribbleLive service.
Their messages - which feigned to be legitimate updates from the live blogging site - contained a link entitled “Watch the Hospital Cam”.
Subscribers who followed this - in the hope of catching a glimpse of the future king outside the Lindo Wing of St Mary's Hospital - would instead have been infected by the Zeus trojan which is designed to steal bank details.
Troy Gill, senior security analyst at web security firm Appriver, said: “These cyber criminals piggy-backed on the news of the royal birth.
“I anticipate they would have been sending tens of millions of emails, if not more than that.
“If you are infected by the Zeus trojan, there is a strong possibility that your banking and any other personal information that you have entered online is going to be harvested. The ultimate goal is to steal your money.”
Video: The verdict on the royal baby's name