43,940 research outputs found
WiFi Epidemiology: Can Your Neighbors' Router Make Yours Sick?
In densely populated urban areas WiFi routers form a tightly interconnected
proximity network that can be exploited as a substrate for the spreading of
malware able to launch massive fraudulent attack and affect entire urban areas
WiFi networks. In this paper we consider several scenarios for the deployment
of malware that spreads solely over the wireless channel of major urban areas
in the US. We develop an epidemiological model that takes into consideration
prevalent security flaws on these routers. The spread of such a contagion is
simulated on real-world data for geo-referenced wireless routers. We uncover a
major weakness of WiFi networks in that most of the simulated scenarios show
tens of thousands of routers infected in as little time as two weeks, with the
majority of the infections occurring in the first 24 to 48 hours. We indicate
possible containment and prevention measure to limit the eventual harm of such
an attack.Comment: 22 pages, 1 table, 4 figure
Non-convex regularization in remote sensing
In this paper, we study the effect of different regularizers and their
implications in high dimensional image classification and sparse linear
unmixing. Although kernelization or sparse methods are globally accepted
solutions for processing data in high dimensions, we present here a study on
the impact of the form of regularization used and its parametrization. We
consider regularization via traditional squared (2) and sparsity-promoting (1)
norms, as well as more unconventional nonconvex regularizers (p and Log Sum
Penalty). We compare their properties and advantages on several classification
and linear unmixing tasks and provide advices on the choice of the best
regularizer for the problem at hand. Finally, we also provide a fully
functional toolbox for the community.Comment: 11 pages, 11 figure
Synesthesia: Detecting Screen Content via Remote Acoustic Side Channels
We show that subtle acoustic noises emanating from within computer screens
can be used to detect the content displayed on the screens. This sound can be
picked up by ordinary microphones built into webcams or screens, and is
inadvertently transmitted to other parties, e.g., during a videoconference call
or archived recordings. It can also be recorded by a smartphone or "smart
speaker" placed on a desk next to the screen, or from as far as 10 meters away
using a parabolic microphone.
Empirically demonstrating various attack scenarios, we show how this channel
can be used for real-time detection of on-screen text, or users' input into
on-screen virtual keyboards. We also demonstrate how an attacker can analyze
the audio received during video call (e.g., on Google Hangout) to infer whether
the other side is browsing the web in lieu of watching the video call, and
which web site is displayed on their screen
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