Hackers have stolen the euro-equivalent of $47 million from European banks using a scary new version of the Trojan virus that spreads from a PC to victim's mobile phone, The Financial Times reported.

The so-called Eurograbber attack hit 30,000 online banking customers in Germany, Italy, Spain and the Netherlands, the FT added.

The attack follows a similar event known as Operation High Roller, which used the same technology to engineer $60 million in fraudulent money transfers at 60 financial institutions, according to Guardian Analytics, an online banking security company.

Eurograbber, however, marks the first time a virus has jumped from a PC to a mobile device and target online banking.

“Not to give kudos to the attackers, but it was a good piece of engineering,” Darrell Burkey, director of intrusion prevention products at Check Point, which sells protection for PCs and networks, told the FT.

“The mobiles they targeted were very common mobiles, and they targeted very successful banks.”

The attack was first detected in August by Check Point and Versafe security services, and targeted Blackberry and Android devices.

Banks were not revealed, though experts say technology could make U.S. vulnerable as well.

U.S. defense officials have said both the government and the private sector risk suffering a major cyber attack that could cripple the economy.

"I read my intel brief every morning at 5:30 a.m. and it's never a very good news story at all," Eric Rosenbach, Deputy Assistant Secretary of Defense for Cyber Policy, told CNBC.

"There are a lot more attacks, and I hate to admit it but I fear that there will be some type of spectacular attack against the United States or one of our allies before there is comprehensive legislation and real appreciation to take this seriously."