Researchers at Secure Computing say they’ve spotted a new Trojan affecting MP3 and Windows Media Audio (WMA) files, as well as Windows Media Video (WMV) files.
The Trojan is spreading quickly to users of P2P file sharing programs such as Limewire, Secure Computing said. When an infected media file is opened, the Windows Media Player is redirected to a malicious site hosting a fake codec and malware. They describe how the media files are infected in the illustration below.
A similar attack was detected in May when McAfee detected infections on more than 360,000 machines.