“…As health sensors like EEGs make their way into commercial-grade HMDs [89], the possibilities of VR (and privileged adversaries) expand dramatically. With these sensors, applications can adjust immersive experiences based on physiological signals that meet users' particular needs in real-time [33], [5], [96], [141] and can help users with rehabilitation treatments [115], [4], [146]. Such improvements, however, will also expose critically sensitive user information, such as physical and mental health conditions [33], [141], [146], behavior [121], [5], [13], language semantics [39], [122], and other sensitive PII like credit cards, PINs, and locations or persons known to the user [72].…”