Symantec Research into Stuxnet Unravels its Payload
New research from Symantec has unveiled another piece of the puzzle relating to the elusive and troublesome Stuxnet malware. It's already known that the malware targets systems that control the PLC, or Programmable Logic Controller, which is a programmable microprocessor-based device typically used to control production machinery on an assembly line.
While researchers have ascertained that Stuxnet comes with a payload that will quietly modify selective bits of PLC code sent out from a controlling workstation, the very specialized nature of the changes has kept them from determining its exact purpose.
According to Symantec, however, the final piece of the mystery is now in place. The key clue appears to be the confirmation that Stuxnet requires the industrial control system to have a component known as the "frequency converter drive." Used to control the speed of a motor, the malware only attempts to meddle with frequency converter drivers that operate at very high speeds.
