Engineers develop new security protocol to protect miniaturized wireless medical implants from cyberthreats

A brain implant designed to help control seizures is hijacked. A pacemaker receives fake signals, disrupting its rhythm. A hacker infiltrates an insulin pump, delivering a fatal overdose. While these scenarios sound like scenes from a sci-fi thriller, such cyberhealth threats are of real concern as medical technology moves toward smart, wirelessly connected implants.

Smart bioelectronic implants promise to revolutionize health care, giving doctors remote access to monitor and adjust treatments. But as these devices become more advanced, they also become more vulnerable. Just like smartphones and bank accounts, medical implants could be targeted by cybercriminals. And when that happens, the consequences could be life-threatening.

At Rice University, electrical and computer engineer Kaiyuan Yang is working to stay ahead of these threats, developing hacker-resistant implants that protect patients from the dark side of medical innovation.

“As biomedical technology advances, the stakes of security are becoming ever more critical,” said Rice University engineer Kaiyuan Yang, who runs the Secure and Intelligent Micro-Systems (SIMS) Lab.

“Imagine a tiny, battery-free medical implant—no bigger than a grain of rice—capable of treating diseases without major surgery or medication regimens.

“Such implants, powered wirelessly and connected to the internet through a wearable hub, could make a huge difference for the autonomy and life quality of people living with chronic conditions like epilepsy or treatment-resistant depression, for instance,” said Yang, an associate professor of electrical and computer engineering at Rice.

Advanced wireless implantable technology could enable doctors to monitor patients’ health and adjust treatment remotely, making the need for on-site testing and treatment obsolete. But Yang warns that with this potential comes a serious risk: Hackers could intercept communications, steal passwords or send fake commands, threatening patient safety.

In recent work presented at the International Solid-State Circuits Conference (ISSCC)—the flagship conference of the Institute of Electrical and Electronics Engineers (IEEE)—Yang and his team unveiled a first-of-its-kind authentication protocol for wireless, battery-free, ultraminiaturized implants that ensures these devices remain protected while still allowing emergency access.

Known as magnetoelectric datagram transport layer security, or ME-DTLS, the protocol exploits a quirk of wireless power transfer, a technology that allows medical implants to be powered externally without a battery. Normally, when the external power source—or in this case the external hub worn by the patient—moves slightly out of alignment, the amount of power the implant receives fluctuates.

“Lateral or side-to-side movement causes a signal misalignment that is usually considered a flaw in these systems, but we turned it into a security feature by transmitting binary values to specific movements with full awareness of the patient,” Yang said.

For example, by coding short movements as a “1” and longer movements as a “0,” the protocol enables users to input a secure access pattern just by moving the external hub in a specific way. This pattern-based input acts like a second authentication factor, much like entering a PIN after using a password or drawing a pattern to unlock a phone.

The overall user experience with the ME-DTLS two-factor authentication closely resembles the process of logging into bank accounts today. Users enter their login credentials, wait for an SMS with a temporary passcode then input this passcode to log in.

This innovation solves two major problems in medical cybersecurity. First, it protects against stolen passwords by requiring a physical confirmation step that cannot be faked remotely.

Second, it ensures emergency responders can access the device without needing preshared credentials. Thus, if a patient is unconscious or unable to provide a password, the implant transmits a temporary authentication signal that can only be detected at close range.

“This ensures that only a nearby authorized device can access the implant,” Yang said. “In emergencies, the implant verifies the responder or doctor by the pattern they draw and gives them access even if there is no internet connection.”

By leveraging an intrinsic feature of wireless power transfer systems, the solution developed by Yang and his team avoids the drawbacks of other security measures for implantable technologies, like the addition of bulky sensors.

The researchers tested the pattern input method with volunteers and found that it correctly recognized the patterns 98.72% of the time, proving their solution is both reliable and easy to use. The team also developed a rapid, low-power method for the implant to send data back out securely and effectively.

“To the best of our knowledge, we are the first to utilize the natural flaw of wireless power transfer to send secure information to the implant and enable secure two-factor authentication in miniaturized implants,” Yang said. “Compared to other medical devices, our design offers the best balance between security, efficiency and reliability.”

For patients, this could mean a future where their medical implants are both secure and accessible when it matters most, offering a simple, intuitive way to ensure that only the right people—whether a doctor, caregiver or emergency responder—can control the technology inside their bodies.