The Haxdoor-IN trojan has been spammed out to PC users via a link in an email message, which offers a free wallchart for football fans who wish to follow their favorite teams in the international soccer tournament.
If users run the malicious program, they risk allowing hackers to gain access to their computer for criminal ends.
All examples of the emails seen so far have been in German, but experts said there was no reason why hackers would not switch to other languages to increase their pool of potential victims.
"The World Cup is one of the biggest sporting events of the year, and fans all over the globe will be following their national team avidly," said Graham Cluley, senior technology consultant for Sophos. "Malware authors are playing on this keen interest and football spirit to try and infect as many people as possible, in an attempt to seize control, steal from, and spy on innocent users' computers."
This is not the first time that hackers have taken advantage of the World Cup competition. A year ago, the Sober-N worm offered tickets to the tournament in an attempt to entrap unprotected users. In 2002, the VBS/Chick-F virus tried to exploit workers desperate to find out the latest scores from the World Cup in South Korea/Japan. In the run-up to the World Cup competition in France in 1998, another football-inspired virus asked infected victims to gamble on who the winner might be, and if the user did not choose the right team triggered a warhead which was capable of wiping all the data off the hard drive.
"It would be no surprise at all if more malware was written as the World Cup rapidly approaches," said Cluley. "Everyone should be careful not to fall foul of football-related viruses and trojan horses, as well as football-related spam and lottery scams."