Back in 2008 a wireless difibrillator was shown to be hackable. At this year's Black Hat conference a presenter showed exactly how to hack into a wireless insulin pump. Both of these demonstrated the ability for lethal hacking of wireless medical devices.
(Here's a shameless plug.) I and a couple other authors put together a book chapter that mentioned our concerns about security of various wireless medical devices available at http://www.intechopen.com/articles/show/title/wireless-telemedicine-system-an-accurate-reliable-and-secure-real-time-health-care.
While no known lethal viruses exists at this point, manual hacks becoming available brings the concept of such viruses one step closer. Perhaps I'm a pessimist, but it seems to me that assassination attempts between countries or companies would have the potential for producing such a virus... or just dumb chance that another virus on wireless networks may trigger serious problems with such a devices.
Do you have similar concerns or am I being overly concerned? Has anyone else seen or discovered lethal security issues with other wireless medical devices?