McDonalds has apologised after sending out MP3 players containing malware as prizes.
The company's Japanese subsidiary sent out the MP3 players after a competition held in August. Customers won the media players after peeling a sticker off the side of a drinks container and checking the winning numbers.
The players shipped with 10 preloaded songs but at some point in the manufacturing stage a version of the QQPass Trojan was installed. The first attempt to use the player with a PC starts the Trojan.
Once activated the Trojan attempts to shut down antivirus software installed on Windows PCs and steal passwords and login details for OICQ, a popular Chinese chat program. It then attempts to email them to a variety of addresses for collection.
"The virus poses an infection risk when the prize is connected to a computer. We therefore recommend consumers not to use the prize," the company said on its website.
