Online gamers are the target of a "pervasive" computer worm which steals personal data, Microsoft has warned.
Online role-play games are also known as MMORPGs
More than 4.9 million have been hit by the worm Taterf in the last six months, a rise of 156% compared to the previous six months.
Worm attacks have doubled while other threats, such as some Trojans and Adware, have decreased.
On average, seven UK computers were infected by a worm every hour during the first half of 2009, the Microsoft Security Intelligence Report said.
Taterf mainly targets massively multiplayer online role-playing games (MMORPGs).
World Of Warcraft
World Of Warcraft, Rainbow Island, Lineage, Gamania and Cabal Online are among the games affected.
In addition to stealing the user's personal information, worms can spread on removable USB sticks and attack all the computers on a work or home network.
Microsoft's global head of security, Vinny Gulluto, told Sky News there are a range of ways gamers and web users can protect their computers.
He warned "new variants show up all the time," but described Taterf as "pervasive".
"You want to make sure you always stay up to date, keep your applications up to date," he said.
"You want to make sure you have a firewall on your machine and run anti-virus software."
Another worm, called Conficker, targeted business users, affecting 5.2 million machines in the first half of 2009.
Online role-play games are also known as MMORPGsMore than 4.9 million have been hit by the worm Taterf in the last six months, a rise of 156% compared to the previous six months.
Worm attacks have doubled while other threats, such as some Trojans and Adware, have decreased.
On average, seven UK computers were infected by a worm every hour during the first half of 2009, the Microsoft Security Intelligence Report said.
Taterf mainly targets massively multiplayer online role-playing games (MMORPGs).
World Of WarcraftWorld Of Warcraft, Rainbow Island, Lineage, Gamania and Cabal Online are among the games affected.
In addition to stealing the user's personal information, worms can spread on removable USB sticks and attack all the computers on a work or home network.
Microsoft's global head of security, Vinny Gulluto, told Sky News there are a range of ways gamers and web users can protect their computers.
He warned "new variants show up all the time," but described Taterf as "pervasive".
"You want to make sure you always stay up to date, keep your applications up to date," he said.
"You want to make sure you have a firewall on your machine and run anti-virus software."
Another worm, called Conficker, targeted business users, affecting 5.2 million machines in the first half of 2009.
