  Virtual reality (VR) telepresence applications and the so-called "metaverse"
promise to be the next major medium of human-computer interaction. However,
with recent studies demonstrating the ease at which VR users can be profiled
and deanonymized, metaverse platforms carry many of the privacy risks of the
conventional internet (and more) while at present offering few of the defensive
utilities that users are accustomed to having access to. To remedy this, we
present the first known method of implementing an "incognito mode" for VR. Our
technique leverages local differential privacy to quantifiably obscure
sensitive user data attributes, with a focus on intelligently adding noise when
and where it is needed most to maximize privacy while minimizing usability
impact. Our system is capable of flexibly adapting to the unique needs of each
VR application to further optimize this trade-off. We implement our solution as
a universal Unity (C#) plugin that we then evaluate using several popular VR
applications. Upon faithfully replicating the most well-known VR privacy attack
studies, we show a significant degradation of attacker capabilities when using
our solution.
