Shoutbox

Such systems require that all computers are linked to it, so that new prices, promotions, stock, etc. is updated automaticly and immediatly. This king of systems are use all over the world in almost all "net-aware" companies.

If only 1 PC was linked, then the system would be far to expensive and would actually be useless.

Of course a big and decent firewall-system needs to be in place. Also, it doesn't help if you install 10 virusscanners. Stick to 1 or 2...

Many of such attacks are done from the inside. But I'm not implying it was in this case though, only that it happens very frequently in many companies...