I Always Feel Like Somebody's Sensing Me! A Framework to Detect, Identify, and Localize Clandestine Wireless Sensors


Akash Deep Singh, University of California, Los Angeles; Luis Garcia, University of California, Los Angeles, and USC ISI; Joseph Noor and Mani Srivastava, University of California, Los Angeles


The increasing ubiquity of low-cost wireless sensors has enabled users to easily deploy systems to remotely monitor and control their environments. However, this raises privacy concerns for third-party occupants, such as a hotel room guest who may be unaware of deployed clandestine sensors. Previous methods focused on specific modalities such as detecting cameras but do not provide a generalized and comprehensive method to capture arbitrary sensors which may be "spying" on a user. In this work, we propose SnoopDog, a framework to not only detect common Wi-Fi-based wireless sensors that are actively monitoring a user, but also classify and localize each device. SnoopDog works by establishing causality between patterns in observable wireless traffic and a trusted sensor in the same space, e.g., an inertial measurement unit (IMU) that captures a user's movement. Once causality is established, SnoopDog performs packet inspection to inform the user about the monitoring device. Finally, SnoopDog localizes the clandestine device in a 2D plane using a novel trial-based localization technique. We evaluated SnoopDog across several devices and various modalities and were able to detect causality for snooping devices 95.2% of the time and localize devices to a sufficiently reduced sub-space.

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@inproceedings {272130,
author = {Akash Deep Singh and Luis Garcia and Joseph Noor and Mani Srivastava},
title = {I Always Feel Like Somebody{\textquoteright}s Sensing Me! A Framework to Detect, Identify, and Localize Clandestine Wireless Sensors},
booktitle = {30th {USENIX} Security Symposium ({USENIX} Security 21)},
year = {2021},
isbn = {978-1-939133-24-3},
pages = {1829--1846},
url = {https://www.usenix.org/conference/usenixsecurity21/presentation/singh},
publisher = {{USENIX} Association},
month = aug,

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