ATLANTA -- Email and Internet content security provider Marshal (www.marshal.com) is warning email users to be wary this Halloween of malicious spam messages playing on the horror-themed holiday.

The Marshal TRACE team has identified a new run of Halloween spam that invites recipients to visit a Web site and download a “dancing skeleton” – a computer program that purports to create a novelty dancing skeleton on your desktop. By visiting the site, users expose themselves to vulnerability exploits and an executable file named “halloween.exe”. This is in reality a copy of the Storm Trojan which compromises the user’s PC and merges it into a botnet – a network of computers that can be commandeered remotely by a controlling server.

The messages arrive under the guise of subject lines such as:

The Storm Trojan first appeared in January 2007 and quickly gained success and notoriety by using the guise of current affairs headlines. More recently, the gang of criminals behind the Storm Trojan has used special events to draw unsuspecting users to trap Web sites. The Web sites are set up specifically to use browser exploits to infect a visitor with a copy of the bot program. The Storm Gang have used topics ranging from the Fourth of July, the NFL season and Greeting Cards as hooks to lure spam recipients to their malicious Web sites.

The Storm botnet is a serious threat and is known to have control over many thousands of PCs. The Marshal TRACE Team estimates that the Storm botnet is the source of up to 20 per cent of all current spam.

“Today’s run of the Storm Trojan using Halloween as its hook is the latest in a long line of social engineering cons used by these criminals,” said Marshal’s VP of Products, Bradley Anstis. “Many of the previous Storm campaigns have exploited distinctly current events such as the Fourth of July and NFL fantasy football picks. This Halloween run of Storm spam will no doubt entice a much wider audience, even beyond the US.”

Marshal Inc.