Rob, you hit the nail on the head. Resource allocation for networking solutions for machines is just not available at a majority of companies. Most electrical tech leads on the machines do not have the IT background which has been long needed for the Ethernet solutions being implemented on the plant floors. IT usually will forbid access across the company wide network and lock the machine down from outside access which ultimately negates features built into the machine's control scheme to make it easier to manage remotely. This topic is and will be a double edged sword.
In response to the question you raise, Jack, I'd postulate two possible reasons. The first might be that the Iran nuclear processing facility presented a high-value target -- there's widespread opinion that one or more government actors was involved in the takedown. Since that plant had Siemens controllers, Siemens became a target. The other is, I've been told by at least one programmer who should know, that Siemens controllers have very strong functionality on the software side as far as their ability to interface with networks. So it's possible that this strength has been used as a point of attack.
It's interesting that this is Siemens again. Is there a particular set of weaknesses in their security implementations, or are they just being more proactive in analysis and getting the info out there at the moment due to the fact that the first system to be hacked happened to be theirs? I've used the S7 for a number of years and always thought it was solid. However, I also wasn't searching this deeply for holes. I remember years ago with the Allen-Bradley PLC-5 series you could open up the .X5 file (I think) in a text editor, run a simple search for a particular string, and there was the password in plain text. I'm sure that hole has been closed, but this is just saying that there is nothing new.
It would be a mistake to take this too lightly. Imagine the chaos that could be created at any number of huge manufacturing plants if a hacker could decipher a product's password and make unauthorized changes to a manufacturing operation.
In plants, there has been a long battle as to who is in charge of the automation system once it becomes completely networked. It's the war between IT and control. The control side says, "We have production goals to meet, don't get in our way." the IT side says, "You're exposed to the world now, you need to pay attention to security." Looks like IT may have a point now. Plants are becoming more vulnerable to outside intrusions.
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