Panda Security said in a statement that BlackAngel.B, a new variant of the BlackAngel worm, has infected a number of users through MSN Messenger.
The malware masks itself as a link to a video called "Fantasma," which means Ghost. If the user clicks on the attachment, a screen image appears with text that translates into: "On the first day, you get scared. On the second, you get desperate. On the third, you look for help. On the fourth, you die."
If initiated, the worm sends a copy of itself to everyone on the user’s contact list.
Users receive messages saying, "Look at that" or "Look at this video," which are followed by a website link from which the worm is downloaded to infect.
The worm’s payload also closes several security applications, including anti-virus programs and firewalls, to avoid detection, Panda’s statement said. The worm also attempts to close operating system tools, such as Windows Task Manager, Control Panel and System Restore.
The worm’s grim message is similar to the plot of Hollywood blockbuster "The Ring," in which everybody who view a certain tape is told they will die in exactly seven days.