Sensors in Heart Devices Could Hold Security Risks

A new study suggests that forged erratic heartbeat signals generated via radio frequency (RF) electromagnetic waves could inhibit needed pacing or induce unnecessary defibrillation shocks.

Researchers from the University of Michigan (U-M; Ann Arbor, USA), the Korea Advanced Institute of Science and Technology (KAIST; Daejeon, Korea), and other institutions tested implanted cardiac defibrillators (ICDs) and pacemakers in open air to determine which radio waveforms could cause interference, since despite the fact these medical devices have security mechanisms, the information the analog sensors receive bypasses their safety layers. The devices convert the input from the sensors directly into digital information that they use to make quick decisions.

The researchers therefore exposed the medical devices to those waveforms in a both a saline bath and a patient simulator. They found that a perpetrator or hacker would need to be five centimeters away to cause interference, suggesting that the human body likely acts as a shield, protecting the medical devices to a large degree. Current guidelines instruct patients to keep potential sources of interference at least 27 centimeters away from their chest. The study was presented at the IEEE Symposium on Security and Privacy, held during May 2013 in San Francisco (CA, USA).

The researchers also found pathways to tamper with consumer electronics. They were able to use specific RF signals to convince the microphone on a phone paired with a Bluetooth headset that a caller was dialing touch-tone selections at an automated banking line; they demonstrated this by changing the call language from English to Spanish. The technique could conceivably be used for other harmful scenarios such as fraudulent money transfers. In another experiment, they canceled out speech on one side of a web-based phone call and replaced it with a song.

“We found that these analog devices generally trust what they receive from their sensors, and that path is weak and could be exploited,” said study presenter Denis Foo Kune, PhD, a U-M postdoctoral researcher and KAIST visiting scholar in computer science and engineering.

“People with pacemakers and defibrillators can remain confident in the safety and effectiveness of their implants,” added coinvestigator Kevin Fu, PhD, a U-M associate professor of electrical engineering and computer science. “Patients already protect themselves from interference by keeping transmitters like phones away from their implants. The problem is that emerging medical sensors worn on the body, rather than implanted, could be more susceptible to this type of interference.”


Related Links:
University of Michigan
Korea Advanced Institute of Science and Technology