As if the attempted Christmas Day terrorist attack wasn’t enough to instill paranoia in the masses. According to a new study by the US Center for Strategic and International Studies, a “cyber cold war” is quietly raging. The study, commissioned by the computer security company McAfee, found that cyber attacks or infiltrations by gangs and state-sponsored hackers have hit more than half of the companies operating critical infrastructure like gas and oil supplies and electrical grids. The news, which comes in the wake of Google’s revelation that it among about 30 western companies victimized by Chinese hackers, does not bode well in tough economic times. According to the study, the attacks cost the world economy $2.4 billion annually.