2011/10/17 by Philip Marquardt, Arunabh Verma, Henry Carter +1 · 2 citations
Computer Science · #Advanced Malware Detection Techniques #User Authentication and Security Systems #Cryptographic Implementations and Security #Accelerometer #Computer science #Microphone #Mobile device #Mobile phone #Information leakage #Camera phone #Geolocation #Phone #Global Positioning System #Real-time computing #Human–computer interaction #Computer vision #Telecommunications #Computer security
paper · doi:10.1145/2046707.2046771
openalex publication_date 2011/10/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
Mobile phones are increasingly equipped with a range of highly responsive sensors. From cameras and GPS receivers to three-axis accelerometers, applications running on these devices are able to experience rich interactions with their environment. Unfortunately, some applications may be able to use such sensors to monitor their surroundings in unintended ways. In this paper, we demonstrate that an application with access to accelerometer readings on a modern mobile phone can use such information to recover text entered on a nearby keyboard. Note that unlike previous emanation recovery papers, the accelerometers on such devices sample at near the Nyquist rate, making previous techniques unworkable. Our application instead detects and decodes keystrokes by measuring the relative physical position and distance between each vibration. We then match abstracted words against candidate dictionaries and record word recovery rates as high as 80%. In so doing, we demonstrate the potential to recover significant information from the vicinity of a mobile device without gaining access to resources generally considered to be the most likely sources of leakage (e.g., microphone, camera).