The new malicious computer program, which picks up where MyDoom, Netsky and Bagle left off, has the capability of waging large-scale cyber attacks using networks of "bot" computers to send spam and porn.
The newly discovered Phatbot worm has so much destructive potential that it has already caught the eye of Homeland Security, which has asked several top security experts to monitor its progress.
According to reports, once the program has made its way onto a "host" computer, it spreads across networks and searches for passwords that are stored on hard drives. The New York Times reports that Phatbot, a variant of an earlier program known as agobot or gaobot, also disables antivirus programs and systems for upgrading software security.
The virus is currently being tagged "low risk" until it begins to spread.
