Biblio

Password vaults are used to store login credentials, usually encrypted by a master password, relieving the user from memorizing a large number of complex passwords. To manage accounts on multiple devices, vaults are often stored at an online service, which substantially increases the risk of leaking the (encrypted) vault. To protect the master password against guessing attacks, previous work has introduced cracking-resistant password vaults based on Honey Encryption. If decryption is attempted with a wrong master password, they output plausible-looking decoy vaults, thus seemingly disabling offline guessing attacks. In this work, we propose attacks against cracking-resistant password vaults that are able to distinguish between real and decoy vaults with high accuracy and thus circumvent the offered protection. These attacks are based on differences in the generated distribution of passwords, which are measured using Kullback-Leibler divergence. Our attack is able to rank the correct vault into the 1.3% most likely vaults (on median), compared to 37.8% of the best-reported attack in previous work. (Note that smaller ranks are better, and 50% is achievable by random guessing.) We demonstrate that this attack is, to a certain extent, a fundamental problem with all static Natural Language Encoders (NLE), where the distribution of decoy vaults is fixed. We propose the notion of adaptive NLEs and demonstrate that they substantially limit the effectiveness of such attacks. We give one example of an adaptive NLE based on Markov models and show that the attack is only able to rank the decoy vaults with a median rank of 35.1%.

The second wave of change presented by the age of mobility, wearables, and IoT focuses on how organizations and enterprises, from a wide variety of commercial areas and industries, will use and leverage the new technologies available. Businesses and industries that don't change with the times will simply cease to exist. Applications need to be powered by cognitive and contextual technologies to support real-time proactive decisions. These decisions will be based on the mobile context of a specific user or group of users, incorporating location, time of day, current user task, and more. Driven by the huge amounts of data produced by mobile and wearables devices, and influenced by privacy concerns, the next wave in computing will need to exploit data and computing at the edge of the network. Future mobile apps will have to be cognitive to 'understand' user intentions based on all the available interactions and unstructured data. Mobile applications are becoming increasingly ubiquitous, going beyond what end users can easily comprehend. Essentially, for both business-to-client (B2C) and business-to-business (B2B) apps, only about 30% of the development efforts appear in the interface of the mobile app. For example, areas such as the collaborative nature of the software or the shortened development cycle and time-to-market are not apparent to end users. The other 70% of the effort invested is dedicated to integrating the applications with back-office systems and developing those aspects of the application that operate behind the scenes. An important, yet often complex, part of the solution and mobile app takes place far from the public eye-in the back-office environment. It is there that various aspects of customer relationship management must be addressed: tracking usage data, pushing out messaging as needed, distributing apps to employees within the enterprise, and handling the wide variety of operational and management tasks-often involving the collection and monitoring of data from sensors and wearable devices. All this must be carried out while addressing security concerns that range from verifying user identities, to data protection, to blocking attempted breaches of the organization, and activation of malicious code. Of course, these tasks must be augmented by a systematic approach and vigilant maintenance of user privacy. The first wave of the mobile revolution focused on development platforms, run-time platforms, deployment, activation, and management tools for multi-platform environments, including comprehensive mobile device management (MDM). To realize the full potential of this revolution, we must capitalize on information about the context within which mobile devices are used. With both employees and customers, this context could be a simple piece of information such as the user location or time of use, the hour of the day, or the day of the week. The context could also be represented by more complex data, such as the amount of time used, type of activity performed, or user preferences. Further insight could include the relationship history with the user and the user's behavior as part of that relationship, as well as a long list of variables to be considered in various scenarios. Today, with the new wave of wearables, the definition of context is being further extended to include environmental factors such as temperature, weather, or pollution, as well as personal factors such as heart rate, movement, or even clothing worn. In both B2E and B2C situations, a context-dependent approach, based on the appropriate context for each specific user, offers a superior tool for working with both employees and clients alike. This mode of operation does not start and end with the individual user. Rather, it takes into account the people surrounding the user, the events taking place nearby, appliances or equipment activated, the user's daily schedule, as well as other, more general information, such as the environment and weather. Developing enterprise-wide, context-dependent, mobile solutions is still a complex challenge. A system of real added-value services must be developed, as well as a comprehensive architecture. These four-tier architectures comprise end-user devices like wearables and smartphones, connected to systems of engagement (SoEs), and systems of record (SoRs). All this is needed to enable data analytics and collection in the context where it is created. The data collected will allow further interaction with employees or customers, analytics, and follow-up actions based on the results of that analysis. We also need to ensure end-to-end (E2E) security across these four tiers, and to keep the data and application contexts in sync. These are just some of the challenges being addressed by IBM Research. As an example, these technologies could be deployed in the retail space, especially in brick-and-mortar stores. Identifying a customer entering a store, detecting her location among the aisles, and cross-referencing that data with the customer's transaction history, could lead to special offers tailor-made for that specific customer or suggestions relevant to her purchasing process. This technology enables real-world implementation of metrics, analytics, and other tools familiar to us from the online realm. We can now measure visits to physical stores in the same way we measure web page hits: analyze time spent in the store, the areas visited by the customer, and the results of those visits. In this way, we can also identify shoppers wandering around the store and understand when they are having trouble finding the product they want to purchase. We can also gain insight into the standard traffic patterns of shoppers and how they navigate a store's floors and departments. We might even consider redesigning the store layout to take advantage of this insight to enhance sales. In healthcare, the context can refer to insight extracted from data received from sensors on the patient, from either his mobile device or wearable technology, and information about the patient's environment and location at that moment in time. This data can help determine if any assistance is required. For example, if a patient is discharged from the hospital for continued at-home care, doctors can continue to remotely monitor his condition via a system of sensors and analytic tools that interpret the sensor readings. This approach can also be applied to the area of safety. Scientists at IBM Research are developing a platform that collects and analyzes data from wearable technology to protect the safety of employees working in construction, heavy industry, manufacturing, or out in the field. This solution can serve as a real-time warning system by analyzing information gathered from wearable sensors embedded in personal protective equipment, such as smart safety helmets and protective vests, and in the workers' individual smartphones. These sensors can continuously monitor a worker's pulse rate, movements, body temperature, and hydration level, as well as environmental factors such as noise level, and other parameters. The system can provide immediate alerts to the worker about any dangers in the work environment to prevent possible injury. It can also be used to prevent accidents before they happen or detect accidents once they occur. For example, with sophisticated algorithms, we can detect if a worker falls based on a sudden difference in elevations detected by an accelerometer, and then send an alert to notify her peers and supervisor or call for help. Monitoring can also help ensure safety in areas where continuous exposure to heat or dangerous materials must be limited based on regulated time periods. Mobile technologies can also help manage events with massive numbers of participants, such as professional soccer games, music festivals, and even large-scale public demonstrations, by sending alerts concerning long and growing lines or specific high-traffic areas. These technologies can be used to detect accidents typical of large-scale gatherings, send warnings about overcrowding, and alert the event organizers. In the same way, they can alleviate parking problems or guide public transportation operators- all via analysis and predictive analytics. IBM Research - Haifa is currently involved in multiple activities as part of IBM's MobileFirst initiative. Haifa researchers have a special expertise in time- and location-based intelligent applications, including visual maps that display activity contexts and predictive analytics systems for mobile data and users. In another area, IBM researchers in Haifa are developing new cognitive services driven from the unique data available on mobile and wearable devices. Looking to the future, the IBM Research team is further advancing the integration of wearable technology, augmented reality systems, and biometric tools for mobile user identity validation. Managing contextual data and analyzing the interaction between the different kinds of data presents fascinating challenges for the development of next-generation programming. For example, we need to rethink when and where data processing and computations should occur: Is it best to leave them at the user-device level, or perhaps they should be moved to the back-office systems, servers, and/or the cloud infrastructures with which the user device is connected? New-age applications are becoming more and more distributed. They operate on a wide range of devices, such as wearable technologies, use a variety of sensors, and depend on cloud-based systems. As a result, a new distributed programming paradigm is emerging to meet the needs of these use-cases and real-time scenarios. This paradigm needs to deal with massive amounts of devices, sensors, and data in business systems, and must be able to shift computation from the cloud to the edge, based on context in close to real-time. By processing data at the edge of the network, close to where the interactions and processing are happening, we can help reduce latency and offer new opportunities for improved privacy and security. Despite all these interactions, data collection, and the analytic insights based upon them-we cannot forget the issues of privacy. Without a proper and reliable solution that offers more control over what personal data is shared and how it is used, people will refrain from sharing information. Such sharing is necessary for developing and understanding the context in which people are carrying out various actions, and to offer them tools and services to enhance their actions. In the not-so-distant future, we anticipate the appearance of ad-hoc networks for wearable technology systems that will interact with one another to further expand the scope and value of available context-dependent data.

Information flow analyses traditionally use the Program Dependence Graph (PDG) as a supporting data-structure. This graph relies on Ferrante et al.'s notion of control dependences to represent implicit flows of information. A limitation of this approach is that it may create O(textbarItextbar x textbarEtextbar) implicit flow edges in the PDG, where I are the instructions in a program, and E are the edges in its control flow graph. This paper shows that it is possible to compute information flow analyses using a different notion of implicit dependence, which yields a number of edges linear on the number of definitions plus uses of variables. Our algorithm computes these dependences in a single traversal of the program's dominance tree. This efficiency is possible due to a key property of programs in Static Single Assignment form: the definition of a variable dominates all its uses. Our algorithm correctly implements Hunt and Sands system of security types. Contrary to their original formulation, which required O(IxI) space and time for structured programs, we require only O(I). We have used our ideas to build FlowTracker, a tool that uncovers side-channel vulnerabilities in cryptographic algorithms. FlowTracker handles programs with over one-million assembly instructions in less than 200 seconds, and creates 24% less implicit flow edges than Ferrante et al.'s technique. FlowTracker has detected an issue in a constant-time implementation of Elliptic Curve Cryptography; it has found several time-variant constructions in OpenSSL, one issue in TrueCrypt and it has validated the isochronous behavior of the NaCl library.

In the field of image processing, it is more complex and challenging task to detect the Human motion in the video and recognize their actions from the video sequences. A novel approach is presented in this paper to detect the human motion and recognize their actions. By tracking the selected object over consecutive frames of a video or image sequences, the different Human actions are recognized. Initially, the background motion is subtracted from the input video stream and its binary images are constructed. Using spatiotemporal interest points, the object which needs to be monitored is selected by enclosing the required pixels within the bounding rectangle. The selected foreground pixels within the bounding rectangle are then tracked using edge tracking algorithm. The features are extracted and using these features human motion are detected. Finally, the different human actions are recognized using K-Nearest Neighbor classifier. The applications which uses this methodology where monitoring the human actions is required such as shop surveillance, city surveillance, airports surveillance and other important places where security is the prime factor. The results obtained are quite significant and are analyzed on the datasets like KTH and Weizmann dataset, which contains actions like bending, running, walking, skipping, and hand-waving.

Online services are increasingly dependent on user participation. Whether it's online social networks or crowdsourcing services, understanding user behavior is important yet challenging. In this paper, we build an unsupervised system to capture dominating user behaviors from clickstream data (traces of users' click events), and visualize the detected behaviors in an intuitive manner. Our system identifies "clusters" of similar users by partitioning a similarity graph (nodes are users; edges are weighted by clickstream similarity). The partitioning process leverages iterative feature pruning to capture the natural hierarchy within user clusters and produce intuitive features for visualizing and understanding captured user behaviors. For evaluation, we present case studies on two large-scale clickstream traces (142 million events) from real social networks. Our system effectively identifies previously unknown behaviors, e.g., dormant users, hostile chatters. Also, our user study shows people can easily interpret identified behaviors using our visualization tool.

Modern world has witnessed a dramatic increase in our ability to collect, transmit and distribute real-time monitoring and surveillance data from large-scale information systems and cyber-physical systems. Detecting system anomalies thus attracts significant amount of interest in many fields such as security, fault management, and industrial optimization. Recently, invariant network has shown to be a powerful way in characterizing complex system behaviours. In the invariant network, a node represents a system component and an edge indicates a stable, significant interaction between two components. Structures and evolutions of the invariance network, in particular the vanishing correlations, can shed important light on locating causal anomalies and performing diagnosis. However, existing approaches to detect causal anomalies with the invariant network often use the percentage of vanishing correlations to rank possible casual components, which have several limitations: 1) fault propagation in the network is ignored; 2) the root casual anomalies may not always be the nodes with a high-percentage of vanishing correlations; 3) temporal patterns of vanishing correlations are not exploited for robust detection. To address these limitations, in this paper we propose a network diffusion based framework to identify significant causal anomalies and rank them. Our approach can effectively model fault propagation over the entire invariant network, and can perform joint inference on both the structural, and the time-evolving broken invariance patterns. As a result, it can locate high-confidence anomalies that are truly responsible for the vanishing correlations, and can compensate for unstructured measurement noise in the system. Extensive experiments on synthetic datasets, bank information system datasets, and coal plant cyber-physical system datasets demonstrate the effectiveness of our approach.

Malware detection has been widely studied by analysing either file dropping relationships or characteristics of the file distribution network. This paper, for the first time, studies a global heterogeneous malware delivery graph fusing file dropping relationship and the topology of the file distribution network. The integration offers a unique ability of structuring the end-to-end distribution relationship. However, it brings large heterogeneous graphs to analysis. In our study, an average daily generated graph has more than 4 million edges and 2.7 million nodes that differ in type, such as IPs, URLs, and files. We propose a novel Bayesian label propagation model to unify the multi-source information, including content-agnostic features of different node types and topological information of the heterogeneous network. Our approach does not need to examine the source codes nor inspect the dynamic behaviours of a binary. Instead, it estimates the maliciousness of a given file through a semi-supervised label propagation procedure, which has a linear time complexity w.r.t. the number of nodes and edges. The evaluation on 567 million real-world download events validates that our proposed approach efficiently detects malware with a high accuracy.

Convolution serves as the basic computational primitive for various associative computing tasks ranging from edge detection to image matching. CMOS implementation of such computations entails significant bottlenecks in area and energy consumption due to the large number of multiplication and addition operations involved. In this paper, we propose an ultra-low power and compact hybrid spintronic-CMOS design for the convolution computing unit. Low-voltage operation of domain-wall motion based magneto-metallic "Spin-Memristor"s interfaced with CMOS circuits is able to perform the convolution operation with reasonable accuracy. Simulation results of Gabor filtering for edge detection reveal \textasciitilde 2.5× lower energy consumption compared to a baseline 45nm-CMOS implementation.

When customers purchase a product or sign up for service from a company, they often are required to agree to a Privacy Policy or Terms of Service agreement. Many of these policies are lengthy, and a typical customer agrees to them without reading them carefully if at all. To address this problem, we have developed a prototype automatic text summarization system which is specifically designed for privacy policies. Our system generates a summary of a policy statement by identifying important sentences from the statement, categorizing these sentences by which of 5 "statement categories" the sentence addresses, and displaying to a user a list of the sentences which match each category. Our system incorporates keywords identified by a human domain expert and rules that were obtained by machine learning, and they are combined in an ensemble architecture. We have tested our system on a sample corpus of privacy statements, and preliminary results are promising.

In the last couple of years, organizations have demonstrated an increased willingness to participate in threat intelligence sharing platforms. The open exchange of information and knowledge regarding threats, vulnerabilities, incidents and mitigation strategies results from the organizations' growing need to protect against today's sophisticated cyber attacks. To investigate data quality challenges that might arise in threat intelligence sharing, we conducted focus group discussions with ten expert stakeholders from security operations centers of various globally operating organizations. The study addresses several factors affecting shared threat intelligence data quality at multiple levels, including collecting, processing, sharing and storing data. As expected, the study finds that the main factors that affect shared threat intelligence data stem from the limitations and complexities associated with integrating and consolidating shared threat intelligence from different sources while ensuring the data's usefulness for an inhomogeneous group of participants.Data quality is extremely important for shared threat intelligence. As our study has shown, there are no fundamentally new data quality issues in threat intelligence sharing. However, as threat intelligence sharing is an emerging domain and a large number of threat intelligence sharing tools are currently being rushed to market, several data quality issues – particularly related to scalability and data source integration – deserve particular attention.

The World Wide Web has become the most common platform for building applications and delivering content. Yet despite years of research, the web continues to face severe security challenges related to data integrity and confidentiality. Rather than continuing the exploit-and-patch cycle, we propose addressing these challenges at an architectural level, by supplementing the web's existing connection-based and server-based security models with a new approach: content-based security. With this approach, content is directly signed and encrypted at rest, enabling it to be delivered via any path and then validated by the browser. We explore how this new architectural approach can be applied to the web and analyze its security benefits. We then discuss a broad research agenda to realize this vision and the challenges that must be overcome.

SSL and TLS are used to secure the most commonly used Internet protocols. As a result, the ecosystem of SSL certificates has been thoroughly studied, leading to a broad understanding of the strengths and weaknesses of the certificates accepted by most web browsers. Prior work has naturally focused almost exclusively on "valid" certificates–those that standard browsers accept as well-formed and trusted–and has largely disregarded certificates that are otherwise "invalid." Surprisingly, however, this leaves the majority of certificates unexamined: we find that, on average, 65% of SSL certificates advertised in each IPv4 scan that we examine are actually invalid. In this paper, we demonstrate that despite their invalidity, much can be understood from these certificates. Specifically, we show why the web's SSL ecosystem is populated by so many invalid certificates, where they originate from, and how they impact security. Using a dataset of over 80M certificates, we determine that most invalid certificates originate from a few types of end-user devices, and possess dramatically different properties than their valid counterparts. We find that many of these devices periodically reissue their (invalid) certificates, and develop new techniques that allow us to track these reissues across scans. We present evidence that this technique allows us to uniquely track over 6.7M devices. Taken together, our results open up a heretofore largely-ignored portion of the SSL ecosystem to further study.

Cross-site scripting (XSS) attacks keep plaguing the Web. Supported by most modern browsers, Content Security Policy (CSP) prescribes the browser to restrict the features and communication capabilities of code on a web page, mitigating the effects of XSS.

This paper puts a spotlight on the problem of data exfiltration in the face of CSP. We bring attention to the unsettling discord in the security community about the very goals of CSP when it comes to preventing data leaks.

As consequences of this discord, we report on insecurities in the known protection mechanisms that are based on assumptions about CSP that turn out not to hold in practice.

To illustrate the practical impact of the discord, we perform a systematic case study of data exfiltration via DNS prefetching and resource prefetching in the face of CSP.

Our study of the popular browsers demonstrates that it is often possible to exfiltrate data by both resource prefetching and DNS prefetching in the face of CSP. Further, we perform a crawl of the top 10,000 Alexa domains to report on the cohabitance of CSP and prefetching in practice. Finally, we discuss directions to control data exfiltration and, for the case study, propose measures ranging from immediate fixes for the clients to prefetching-aware extensions of CSP.

Modern web browsers are incredibly complex, with millions of lines of code and over one thousand JavaScript functions and properties available to website authors. This work investigates how these browser features are used on the modern, open web. We find that JavaScript features differ wildly in popularity, with over 50% of provided features never used on the web's 10,000 most popular sites according to Alexa We also look at how popular ad and tracking blockers change the features used by sites, and identify a set of approximately 10% of features that are disproportionately blocked (prevented from executing by these extensions at least 90% of the time they are used). We additionally find that in the presence of these blockers, over 83% of available features are executed on less than 1% of the most popular 10,000 websites. We further measure other aspects of browser feature usage on the web, including how many features websites use, how the length of time a browser feature has been in the browser relates to its usage on the web, and how many security vulnerabilities have been associated with related browser features.

Browser fingerprinting is a widely used technique to uniquely identify web users and to track their online behavior. Until now, different tools have been proposed to protect the user against browser fingerprinting. However, these tools have usability restrictions as they deactivate browser features and plug-ins (like Flash) or the HTML5 canvas element. In addition, all of them only provide limited protection, as they randomize browser settings with unrealistic parameters or have methodical flaws, making them detectable for trackers. In this work we demonstrate the first anti-fingerprinting strategy, which protects against Flash fingerprinting without deactivating it, provides robust and undetectable anti-canvas fingerprinting, and uses a large set of real word data to hide the actual system and browser properties without losing usability. We discuss the methods and weaknesses of existing anti-fingerprinting tools in detail and compare them to our enhanced strategies. Our evaluation against real world fingerprinting tools shows a successful fingerprinting protection in over 99% of 70.000 browser sessions.

Modern websites use multiple authentication cookies to allow visitors to the site different levels of access. The complexity of modern web applications can make it difficult for a web application programmer to ensure that the use of authentication cookies does not introduce vulnerabilities. Even when a programmer has access to all of the source code, this analysis can be challenging; the problem becomes even more vexing when web programmers cobble together off-the-shelf libraries to implement authentication. We have assembled a checklist for modern web programmers to verify that the cookie based authentication mechanism is securely implemented. Then, we developed a tool, Newton, to help a web application programmer to identify authentication cookies for specific parts of the website and to verify that they are securely implemented according to the checklist. We used Newton to analyze 149 sites, including the Alexa top-200 and many other popular sites across a range of categories including search, shopping, and finance. We found that 113 of them–-including high-profile sites such as Yahoo, Amazon, and Fidelity–-were vulnerable to hijacking attacks. Many websites have already acknowledged and fixed the vulnerabilities that we found using Newton and reported to them.

Content Security Policy (CSP) is an emerging W3C standard introduced to mitigate the impact of content injection vulnerabilities on websites. We perform a systematic, large-scale analysis of four key aspects that impact on the effectiveness of CSP: browser support, website adoption, correct configuration and constant maintenance. While browser support is largely satisfactory, with the exception of few notable issues, our analysis unveils several shortcomings relative to the other three aspects. CSP appears to have a rather limited deployment as yet and, more crucially, existing policies exhibit a number of weaknesses and misconfiguration errors. Moreover, content security policies are not regularly updated to ban insecure practices and remove unintended security violations. We argue that many of these problems can be fixed by better exploiting the monitoring facilities of CSP, while other issues deserve additional research, being more rooted into the CSP design.

Process-based isolation, suggested by several research prototypes, is a cornerstone of modern browser security architectures. Google Chrome is the first commercial browser that adopts this architecture. Unlike several research prototypes, Chrome's process-based design does not isolate different web origins, but primarily promises to protect "the local system" from "the web". However, as billions of users now use web-based cloud services (e.g., Dropbox and Google Drive), which are integrated into the local system, the premise that browsers can effectively isolate the web from the local system has become questionable. In this paper, we argue that, if the process-based isolation disregards the same-origin policy as one of its goals, then its promise of maintaining the "web/local system (local)" separation is doubtful. Specifically, we show that existing memory vulnerabilities in Chrome's renderer can be used as a stepping-stone to drop executables/scripts in the local file system, install unwanted applications and misuse system sensors. These attacks are purely data-oriented and do not alter any control flow or import foreign code. Thus, such attacks bypass binary-level protection mechanisms, including ASLR and in-memory partitioning. Finally, we discuss various full defenses and present a possible way to mitigate the attacks presented.

The market of wearable healthcare monitoring devices has exploded in recent years as healthcare consciousness has increased. These types of devices usually consist of several biosensors, which can be worn on human bodies, such as the head, arms, and feet. The health status of a user can be analyzed according to the user's real-time vital signs that are collected from different biosensors. Due to personal medical data being transmitted through a wireless network, the data have to be encrypted. In this paper, a key agreement protocol for biosensors within Wireless Body Sensor Networks (WBSN) has been proposed based on the n-Party Diffie-Hellman key exchange protocol. In order to prevent the man-in-the-middle attacks, we have used Advance Encryption Standard (AES) encryption with Electrocardiography-based (ECG-based) keys to secure the key exchange procedures. The security and performance analysis show the feasibility of the proposed method.

Proliferation of electronics and their increasing connectivity pose formidable challenges for information security. At the most fundamental level, nanostructures and nanomaterials offer an unprecedented opportunity to introduce new approaches to securing electronic devices. First, we discuss engineering nanomaterials, (e.g., carbon nanotubes (CNTs), graphene, and layered transition metal dichalcogenides (TMDs)) to make unclonable cryptographic primitives. These security primitives not only can supplement existing solutions in silicon integrated circuits (ICs) but can also be used for emerging applications in flexible and wearable electronics. Second, we discuss security engineering of advanced nanostructures such as reactive materials.

The proliferation of wearable devices, e.g., smartwatches and activity trackers, with embedded sensors has already shown its great potential on monitoring and inferring human daily activities. This paper reveals a serious security breach of wearable devices in the context of divulging secret information (i.e., key entries) while people accessing key-based security systems. Existing methods of obtaining such secret information relies on installations of dedicated hardware (e.g., video camera or fake keypad), or training with labeled data from body sensors, which restrict use cases in practical adversary scenarios. In this work, we show that a wearable device can be exploited to discriminate mm-level distances and directions of the user's fine-grained hand movements, which enable attackers to reproduce the trajectories of the user's hand and further to recover the secret key entries. In particular, our system confirms the possibility of using embedded sensors in wearable devices, i.e., accelerometers, gyroscopes, and magnetometers, to derive the moving distance of the user's hand between consecutive key entries regardless of the pose of the hand. Our Backward PIN-Sequence Inference algorithm exploits the inherent physical constraints between key entries to infer the complete user key entry sequence. Extensive experiments are conducted with over 5000 key entry traces collected from 20 adults for key-based security systems (i.e. ATM keypads and regular keyboards) through testing on different kinds of wearables. Results demonstrate that such a technique can achieve 80% accuracy with only one try and more than 90% accuracy with three tries, which to our knowledge, is the first technique that reveals personal PINs leveraging wearable devices without the need for labeled training data and contextual information.

Recent computing paradigms like cloud computing and big data have become very appealing to outsource computation and storage, making it easier to realize personalized and patient centric healthcare through real-time analytics on user data. Although these technologies can significantly complement resource constrained mobile and wearable devices to store and process personal health information, privacy concerns are keeping patients from reaping the full benefits. In this paper, we present and evaluate a practical smart-watch based lifelog application for diabetics that leverages the cloud and homomorphic encryption for caregivers to analyze blood glucose, insulin values, and other parameters in a privacy friendly manner to ensure confidentiality such that even a curious cloud service provider remains oblivious of sensitive health data.

In this demo, we will display a smartphone authentication system that can automatically validate every touch interaction made on a smartphone using a smart watch worn by the phone's owner. The IMU sensors on a smart watch monitor the motion of the hand for specific signal characteristics, which is relayed to the phone. If the signal features match certain criteria then the touch is authenticated and the phone responds appropriately. If not, the phone's screen remains locked/unresponsive to the touch action. The challenge here is to be able to validate every touch gesture within acceptable limits of human perception.

Wearable devices, such as smartwatches, are furnished with state-of-the-art sensors that enable a range of context-aware applications. However, malicious applications can misuse these sensors, if access is left unaudited. In this paper, we demonstrate how applications that have access to motion or inertial sensor data on a modern smartwatch can recover text typed on an external QWERTY keyboard. Due to the distinct nature of the perceptible motion sensor data, earlier research efforts on emanation based keystroke inference attacks are not readily applicable in this scenario. The proposed novel attack framework characterizes wrist movements (captured by the inertial sensors of the smartwatch worn on the wrist) observed during typing, based on the relative physical position of keys and the direction of transition between pairs of keys. Eavesdropped keystroke characteristics are then matched to candidate words in a dictionary. Multiple evaluations show that our keystroke inference framework has an alarmingly high classification accuracy and word recovery rate. With the information recovered from the wrist movements perceptible by a smartwatch, we exemplify the risks associated with unaudited access to seemingly innocuous sensors (e.g., accelerometers and gyroscopes) of wearable devices. As part of our efforts towards preventing such side-channel attacks, we also develop and evaluate a novel context-aware protection framework which can be used to automatically disable (or downgrade) access to motion sensors, whenever typing activity is detected.

Securely pairing wearables with another device is the key to many promising applications, such as mobile payment, sensitive data transfer and secure interactions with smart home devices. This paper presents Touch-And-Guard (TAG), a system that uses hand touch as an intuitive manner to establish a secure connection between a wristband wearable and the touched device. It generates secret bits from hand resonant properties, which are obtained using accelerometers and vibration motors. The extracted secret bits are used by both sides to authenticate each other and then communicate confidentially. The ubiquity of accelerometers and motors presents an immediate market for our system. We demonstrate the feasibility of our system using an experimental prototype and conduct experiments involving 12 participants with 1440 trials. The results indicate that we can generate secret bits at a rate of 7.84 bit/s, which is 58% faster than conventional text input PIN authentication. We also show that our system is resistant to acoustic eavesdroppers in proximity.