The bug began spreading on Wednesday night and has affected a small number of companies in Italy, Germany and France, published reports said. Tagged "Cartolina" (postcard), the virus changes the default page of Internet Explorer to that of an Italian music Web site, http://www.vije.it, and sends copies of itself to everyone in the victim's address book, the reports said.
"The damage appears to be limited," a spokeswoman for Seat-Tin.it SpA, Italy's largest Internet service provider said. "It just reproduces itself and modifies the home page. It hasn't caused the kind of havoc we saw six months ago with the 'I Love You' bug."
The infectious attachment is named "Cartolina.VBS" and has a subject line reading: "C'e una cartolina per te!" (There's a postcard for you). The body of the message reads "Ciao, un tuo amico ti ha spedito una cartolina virtuale ... mooolto particolare!" (Hi, a friend has sent you a virtual postcard... veeery special!). The Seat-Tin.it spokeswoman said the company had no data on the extent of damage caused by the worm, but was advising its 4 million customers to avoid opening unexpected attachments ending in .vbs, .vba and .exe.
"I haven't received any information about the presence of this virus," said Massimo Vignoli, head of network security at the Italian Bankers' Association (ABI). "If the problem were serious, we would hear about it immediately. It looks as though it should be fairly easy to fix, but we will have to wait and see whether there is anything more to it that has not yet emerged."
"The virus doesn't seem to have had much impact," said Stefano Lamborghini, secretary general of the Association of Italian Internet Providers (AIIP). "I haven't been notified about it by any of the providers."
The virus was unlikely to spread globally because it is written in Italian, security experts said.