The bad decision was installing antivirus software. Otherwise, most any modern OS would be fine. This machine probably shouldn't be connected to a network (if it was), the USB ports should be disabled; data can come off on burned CDs, autorun should be disabled, etc. That's how you deal with IA concerns on a standalone mission-critical system, not by installing antivirus.
Having their software run in a Windows ecosystem that they do not have strict configuration management control over was a bad decision and on the basis of this failure report. That it did not result in patient injury or death was fortunate but is certainly not guaranteed.
No matter what OS you choose it is vulnerable to viruses. You and I will agree that the odds are your Windows system is much more at risk by at least an order of magnitude. But the IA people who demanded that this system run antivirus are just as likely to demand that Linux run antivirus, simply because the vulnerability theoretically exists and making that demand fulfills their CYA requirements. I've worked on standalone Linux systems that IA demanded have antivirus.
> Either you own that decision, and as part of your support your tool provides the necessary antivirus and you also insure through testing configuration management that its configured appropriately, or you choose a different option up to an including writing your own system to manage the "time critical bits".
According to the article, the software runs on the user's hardware. While they certainly could have made a decision to provide their own controlled hardware, it's entirely possible that hospital was not open to that option for cost reasons, for IT management reasons, whatever.
> No matter what OS you choose it is vulnerable to
> viruses.
It is a bit more nuanced than that. While it is true that absolute security is generally deemed impossible, if you use a widely deployed operating system in your device there are both a number of actors trying to compromise it for different reasons, and a number of examples that can be acquired for testing different exploits.By writing just enough "OS" to achieve your goals in an embedded system, and then designing a clean access API through which you cannot affect the underlying code (no "here download this new firmware" call) you can avoid that particular threat vector.
it is a common misconception that Windows is still worse a platform than Linux when it comes to security. Not trolling ... I'm using Linux since '96 and built my life and career on it. Opinion of some people in infosec circles (@thegrugq @csoghoian ...) is that Windows no longer lags behind:
https://grugq.github.io/presentations/COMSEC%20beyond%20encr...
This may be theoretically true, but it is not practically the case. There is a reason Linux and OS X users almost never use antivirus software.
Using Windows on a medical device is inexcusable. It's a heart monitor, not a game system.
That's not true for what those systems should be really running which is separation kernel platforms. These isolated tasks in partitions using high-assurance kernels designed to not fail in every way you can think of and with almost no code to hit. The apps even donate their own resources for kernel calls. Interface is in untrusted VM that sends checked commands to real software running on isolated partition optionally on Ada or Java runtime for memory-safety. Anti-virus is not available and not necessary given the untrusted part is strongly contained & the trusted part is memory safe.
http://www.ghs.com/products/safety_critical/integrity-do-178...
https://os.inf.tu-dresden.de/papers_ps/nizza.pdf
Just a matter of using right tools for the job. Any medical device using Windows or any other complex OS isn't doing it right. Even OpenBSD would've been a better choice given it rarely is hacked, crashes, or needs updates. Antivirus software wouldn't run as it's not available for these. It would be a network appliance or something that didn't affect running system.
And I would have followed the same steps you mentioned. The machine could work with Windows.
Windows CE might have been a better pick, so you can have things like RO filesystem, etc
"There is no reason to use Windows" is, as you mentioned, not a bad decision in itself, but since they do it the lazy way, it is awful. Not sure if there's an out-of-the-box way of firewalling everything in the Windows versions available at the time that machine was built
* GUI dev tools were an order of magnitude better than under linux
* nidaq (very common daq and dio cards) didn't have or had flaky linux drivers. usb may be a better choice today but was not then available. Plus it's convenient/less expensive to push functionality to the computer side and minimize embedded development.
* in the beginning (though we fixed this mistake), we shipped software, our machine, and a ni-daq card; users provided a computer. This was a nightmare. We ended up shipping whole computers custom built by Dell to our specs with ni-daq cards installed (and later glued in to prevent them slipping out during shipping) plus our custom system images. At the time, I don't think Dell would do this for linux; you could find other vendors that would, but they weren't easy to work with or much more expensive.
* Nobody is eager to switch OSes because every software update to the machine has to be FDA certified (ie kiss at least $100k goodbye), so the company is very risk averse. Beyond even the cost to rewrite what has evolved into a relatively complicated gui app.
* As mentioned elsewhere, once you leave windows you have to train people to use linux guis that historically had window managers / gui toolkits that didn't work like windows.
All of the above is complicated by the fact most of these medical device companies pay their devs shit and have trouble hiring good devs. (Engineering shortage, obviously!)
Interesting. Does that imply that every Windows update Microsoft releases has been FDA-certified already?
I wish I was kidding.
I know that "tired person in a hurry" is a trope, but considering how masochistic the health professions are about sleep, it really applies here.