The first subject lines concerned weather events in Europe -- hence the name. More recent subject lines mention severe U.S. weather, Chinese missiles, Russian missiles, Saddam Hussein (alive in some Elvis-like fashion), a purported terrorist attack on the Supreme Court and/or Congress, a paroled murderer in Michigan, and the always popular naked marauding teenagers.

Some quarters have reported finding the Trojan in romance-themed messages, presumably to take advantage of the Valentine's Day rush. An earlier infection dropped by the Nuwar downloader carried New Year's greetings, and the .exe claimed to be a greeting card or postcard. A reader of F-Secure's "News from the Lab" blog points out that the latest list of subjects bears a resemblance to a list of cards in the romance category at 2000greetings.com, indicating that the perpetrators may be casting their nets even wider for "inspiration."

What's the payload?

The message (in the case of spam) is accompanied by a compressed .exe file of about 29KB. The name of that file also varies, though not as much as the subject lines: Full Clip.exe, Full Story.exe, Video.exe, Read More.exe and other variations have been spotted.

If the user clicks on the file, a few things happen. The program installs two .ini files, peers.ini and wincom32.ini, and a system file called wincom32.sys. That's the Trojan, and it has rootkit capabilities (enabling the infection to disguise itself and its processes) to boot.