  The landscape of miniaturized wireless biomedical devices (MWBDs) is rapidly
expanding as proactive mobile healthcare proliferates. MWBDs are diverse and
include various injectable, ingestible, implantable, and wearable devices.
While the growth of MWBDs increases the flexibility of medical services, the
adoption of these technologies brings privacy and security risks for their
users. MWBDs can operate with sensitive, private information and affect
patients through the use of stimulation and drug delivery. Therefore, these
devices require trust and need to be secure. Embedding protective mechanisms
into MWBDs is challenging because they are restricted in size, power budget, as
well as processing and storage capabilities. Nevertheless, MWBDs need to be at
least minimally securable in the face of evolving threats. The main intent of
this work is to make the primary stakeholders of MWBDs aware of associated
risks and to help the architects and the manufacturers of MWBDs protect their
emerging designs in a repeatable and structured manner. Making MWBDs securable
begins with performing threat modeling. This paper introduces a domain-specific
qualitative-quantitative threat model dedicated to MWBDs. The proposed model is
then applied to representative case studies from each category of MWBDs.
