Consumers and businesses need to be extra vigilant against virus threats from hackers taking advantage of World Cup fever, according to a security warning from Sophos.

"In the past we've seen viruses exploiting the popularity of celebrities like Anna Kournikova. David Beckham or Wayne Rooney could be next," Graham Cluley, senior technology consultant at Sophos, told vnunet.com.

"Businesses need to ensure that staff are not downloading unknown code to their computers. The code may pretend to offer soccer coverage, but actually installs spyware.

"Even if the code isn't malicious, it may be eating up valuable internet bandwidth. For example, many businesses will be reluctant to give their staff free-for-all access to the BBC online World Cup games because of the potential hit on their network resources and bandwidth."

The answer, according to Cluley, could be a good old portable TV. "Portable TVs may be the most sensible way of letting your workers watch the football without disrupting your network or introducing security risks," he said.

Cluley dismissed newspaper reports of the Yagnuul World Cup virus as misleading. "Yagnuul is actually related to the Premiership," he said. "It was first seen about a month ago."

However, the threat of World Cup-related malware and infected emails should not be ignored.

The latest example of a malicious attack using the World Cup as a disguise is the W32/Zasran worm which spread last month, carried by a German-language email offering tickets for matches.

The email, which was headed 'WM-Tickets' or 'Weltmeisterschaft', contained malicious code that allowed hackers to steal information and break into compromised PCs.

Hackers began taking advantage of the 2006 World Cup long before the first game kicked off.

A year ago, the widespread Sober-N worm claimed that people had won free tickets to the tournament. Infected computers were then used to send out Nazi-related spam.

Scammers have even begun preparing for the 2010 World Cup in South Africa. Sophos has come across emails that claim to come from a FIFA-sponsored lottery, but which try to steal people's bank details.

During the last World Cup in 2002, the VBS/Chick-F virus exploited workers in South Korea and Japan desperate to find out the latest scores.

Back in 1998, a virus asked victims to gamble on the winning team in France. If the user failed to choose the right team, a payload was triggered that could wipe all the data off their hard drive.