  Fifty study participants playtested an innocent-looking "escape room" game in
virtual reality (VR). Within just a few minutes, an adversarial program had
accurately inferred over 25 of their personal data attributes, from
anthropometrics like height and wingspan to demographics like age and gender.
As notoriously data-hungry companies become increasingly involved in VR
development, this experimental scenario may soon represent a typical VR user
experience. Since the Cambridge Analytica scandal of 2018, adversarially
designed gamified elements have been known to constitute a significant privacy
threat in conventional social platforms. In this work, we present a case study
of how metaverse environments can similarly be adversarially constructed to
covertly infer dozens of personal data attributes from seemingly anonymous
users. While existing VR privacy research largely focuses on passive
observation, we argue that because individuals subconsciously reveal personal
information via their motion in response to specific stimuli, active attacks
pose an outsized risk in VR environments.
