SQL Slammer (also known as Helkern or Sapphire) is a worm that spreads over the Internet that causes multiple errors.
Payloads and History
It was a worm that basically slew down the Internet traffic and crashed multiple servers. The worm infected the servers over UDP and fit themselves into a single packet, thereby slipping through all the ports and spy them over the Internet traffic and routers not functioning. This worm created major problems during that year and resulted in the worst case scenario in attack field. Among its list of victims; Bank of America's ATMs, a 911 emergency response system in Washington State, and perhaps most disturbingly, a nuclear plant in Ohio.