Antivirus Software and the Hardwired Virus

There is an increasing threat of a completely new kind of computer virus. It could prove more lethal than anything we have seen to date. If unleashed it could disable communications infrastructure, air traffic control, surveillance satellites and GPS, to name just a few of the dangers. This new virus is a hardwired virus that might have been inserted in millions of microchips used in these systems. If it has not yet been inserted yet there is a growing menace that it might be in the future. The virus could be programmed to trigger at a certain time, or a trigger signal could be sent over the internet. If this does happen then we will need a completely new kind of antivirus software to deal with it.

This is not science fiction. There is real concern amongst governments and substantial research is being carried out on possible countermeasures.

How is such a thing as a hardware virus possible? The reason the threat is so real is that many of today's microchips and not designed by a single organisation. The latest generation of chips are highly complex, and carry out many functions on a single device. Only part of the chip will be a processor; there is embedded memory, embedded wireless communications, embedded control system, embedded firmware, and a host of other embedded functions. This kind of microchip is called a System-on-Silicon or SOS chip. It may be manufactured a specific semiconductor company, Intel for instance, however the design will have come from many different organisations. Each function on the chip is called an Intellectual Property Block, or IP block. There are many semiconductor companies, generally call "Fabless Semiconductor Houses" which do not make chips at all; they just design these blocks. The blocks themselves are quite likely designed by assembling sub-blocks and so on, ultimately down to what are called cells. Because design is such a time consuming, difficult and costly operation many IP blocks are made to be reusable and a single one might be used in very different chips.

Thus, for a chip being used in say air traffic control systems, many different organisations and hundreds of designers may have been involved. There is ample opportunity for someone along the line to have inserted some malicious hardwired code that has not yet been discovered.