11 research outputs found
PowerSpy: Location Tracking using Mobile Device Power Analysis
Modern mobile platforms like Android enable applications to read aggregate
power usage on the phone. This information is considered harmless and reading
it requires no user permission or notification. We show that by simply reading
the phone's aggregate power consumption over a period of a few minutes an
application can learn information about the user's location. Aggregate phone
power consumption data is extremely noisy due to the multitude of components
and applications that simultaneously consume power. Nevertheless, by using
machine learning algorithms we are able to successfully infer the phone's
location. We discuss several ways in which this privacy leak can be remedied.Comment: Usenix Security 201
OSS: Using Online Scanning Services for Censorship Circumvention
Abstract. We introduce the concept of a web-based online scanning service, or OSS for short, and show that these OSSes can be covertly used as proxies in a censorship circumvention system. Such proxies are suitable both for short one-time rendezvous messages and bulk bidirectional data transport. We show that OSSes are widely available on the Internet and blocking all of them can be difficult and harmful. We measure the number of round trips and the amount of data that can be pushed through various OSSes and show that we can achieve throughputs of about 100 KB/sec. To demonstrate the effectiveness of our approach we built a system for censored users to communicate with blocked Tor relays using available OSS providers. We report on its design and performance.