Lincoln, Yvonna, and Egon Guba, "Postpositivism and the Naturalist Paradigm," pp. 14-46 in Yvonna Lincoln and Egon Guba, Naturalistic Inquiry . Beverly Hills, CA: Sage, 1985.*

Today’s smartphone operating systems frequently fail to provide users with visibility into how third-party applications collect and share their private data. We address these shortcomings with TaintDroid, an efficient, system-wide dynamic taint tracking and analysis system capable of simultaneously tracking multiple sources of sensitive data. TaintDroid enables realtime analysis by leveraging Android’s virtualized execution environment. TaintDroid incurs only 32p performance overhead on a CPU-bound microbenchmark and imposes negligible overhead on interactive third-party applications. Using TaintDroid to monitor the behavior of 30 popular third-party Android applications, in our 2010 study we found 20 applications potentially misused users’ private information; so did a similar fraction of the tested applications in our 2012 study. Monitoring the flow of privacy-sensitive data with TaintDroid provides valuable input for smartphone users and security service firms seeking to identify misbehaving applications.

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TaintDroid: An Information-Flow Tracking System for Realtime Privacy Monitoring on Smartphones

Explainable Artificial Intelligence (XAI): Concepts, Taxonomies, Opportunities and Challenges toward Responsible AI

National Institute of Standards and Technology における超伝導研究及び生活

Today's smartphone operating systems frequently fail to provide users with adequate control over and visibility into how third-party applications use their private data. We address these shortcomings with TaintDroid, an efficient, system-wide dynamic taint tracking and analysis system capable of simultaneously tracking multiple sources of sensitive data. TaintDroid provides realtime analysis by leveraging Android's virtualized execution environment. TaintDroid incurs only 14% performance overhead on a CPU-bound micro-benchmark and imposes negligible overhead on interactive third-party applications. Using TaintDroid to monitor the behavior of 30 popular third-party Android applications, we found 68 instances of potential misuse of users' private information across 20 applications. Monitoring sensitive data with TaintDroid provides informed use of third-party applications for phone users and valuable input for smartphone security service firms seeking to identify misbehaving applications.

/pdf/taintdroid-an-information-flow-tracking-system-for-realtime-3fnz9lwdso.pdf

TaintDroid: an information-flow tracking system for realtime privacy monitoring on smartphones

We show how to significantly speed-up the encryption portion of some public-key cryptosystems by the simple expedient of allowing a sender to maintain state that is re-used across different encryptions. In particular we present stateful versions of the DHIES and KurosawaDesmedt schemes that each use only one exponentiation to encrypt, as opposed to two and three respectively in the original schemes, yielding the fastest discrete-log based public-key encryption schemes known in the random-oracle and standard models respectively. The schemes are proven to meet an appropriate extension of the standard definition of IND-CCA security that takes into account novel types of attacks possible in the stateful setting. Dept. of Computer Science & Engineering, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA. E-Mail: mihir@cs.ucsd.edu. URL: http://www-cse.ucsd.edu/users/mihir. Supported in part by NSF grant CNS-0524765 and a gift from Intel Corporation. Dept. of Computer Science & Engineering, University of Washington, AC101 Paul G. Allen Center, Box 352350, 185 Stevens Way, Seattle, WA 98195-2350. E-mail: yoshi@cs.washington.edu. URL: http://www.cs.washington. edu/homes/yoshi. Work done while at UCSD, supported in part by grants of first author. Dept. of Computer Science, New York University, Courant Institute, 251 Mercer Street, New York, NY 10012, USA. E-mail: shoup@cs.nyu.edu. URL: http://www.shoup.net. Supported in part by NSF grant CCR-0310297.

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Stateful Public-Key Cryptosystems: How to Encrypt with One 160-bit Exponentiation.

Since December 2019, the COVID-19 pandemic has caused people around the world to exercise social distancing, which has led to an abrupt rise in the adoption of remote communications for working, socializing, and learning from home. As remote communications will outlast the pandemic, it is crucial to protect users' security and respect their privacy in this unprecedented setting, and that requires a thorough understanding of their behaviors, attitudes, and concerns toward various aspects of remote communications. To this end, we conducted an online study with 220 worldwide Prolific participants. We found that privacy and security are among the most frequently mentioned factors impacting participants' attitude and comfort level with conferencing tools and meeting locations. Open-ended responses revealed that most participants lacked autonomy when choosing conferencing tools or using microphone/webcam in their remote meetings, which in several cases contradicted their personal privacy and security preferences. Based on our findings, we distill several recommendations on how employers, educators, and tool developers can inform and empower users to make privacy-protective decisions when engaging in remote communications.

Understanding Privacy Attitudes and Concerns Towards Remote Communications During the COVID-19 Pandemic

Direct-to-consumer (DTC) genetic testing companies have provided personal genotyping services to millions of customers. Customers mail saliva samples to DTC service providers to have their genotypes analyzed and receive back their raw genetic data. Both consumers and the DTC companies use the results to perform ancestry analyses, relative matching, trait prediction, and estimate predisposition to disease, often relying on genetic databases composed of the data from millions of other DTC-genotyped individuals. While the digital integrity risks to this type of data have been explored, we considered whether data integrity issues could manifest upstream of data generation through physical manipulation of DNA samples themselves, for example by adding synthetic DNA to a saliva sample (“spiked samples”) prior to sample processing by a DTC company. Here, we investigated the feasibility of this scenario within the standard DTC genetic testing pipeline. Starting with the purchase of off-the-shelf DTC genetic testing kits, we found that synthetic DNA can be used to precisely manipulate the results of saliva samples genotyped by a popular DTC genetic testing service and that this method can be used to modify arbitrary single nucleotide polymorphisms (SNPs) in multiplex to create customized doctored genetic profiles. This capability has implications for the use of DTC-generated results and the outcomes of their downstream analyses.

Doctoring Direct-to-Consumer Genetic Tests with DNA Spike-Ins

The computer security research community regularly tackles ethical questions. The field of ethics / moral philosophy has for centuries considered what it means to be"morally good"or at least"morally allowed / acceptable". Among philosophy's contributions are (1) frameworks for evaluating the morality of actions -- including the well-established consequentialist and deontological frameworks -- and (2) scenarios (like trolley problems) featuring moral dilemmas that can facilitate discussion about and intellectual inquiry into different perspectives on moral reasoning and decision-making. In a classic trolley problem, consequentialist and deontological analyses may render different opinions. In this research, we explicitly make and explore connections between moral questions in computer security research and ethics / moral philosophy through the creation and analysis of trolley problem-like computer security-themed moral dilemmas and, in doing so, we seek to contribute to conversations among security researchers about the morality of security research-related decisions. We explicitly do not seek to define what is morally right or wrong, nor do we argue for one framework over another. Indeed, the consequentialist and deontological frameworks that we center, in addition to coming to different conclusions for our scenarios, have significant limitations. Instead, by offering our scenarios and by comparing two different approaches to ethics, we strive to contribute to how the computer security research field considers and converses about ethical questions, especially when there are different perspectives on what is morally right or acceptable.

Ethical Frameworks and Computer Security Trolley Problems: Foundations for Conversations

Online hate and harassment poses a threat to the digital safety of people globally. In light of this risk, there is a need to equip as many people as possible with advice to stay safer online. We interviewed 24 experts to understand what threats and advice internet users should prioritize to prevent or mitigate harm. As part of this, we asked experts to evaluate 45 pieces of existing hate-and-harassment-specific digital-safety advice to understand why they felt advice was viable or not. We find that experts frequently had competing perspectives for which threats and advice they would prioritize. We synthesize sources of disagreement, while also highlighting the primary threats and advice where experts concurred. Our results inform immediate efforts to protect users from online hate and harassment, as well as more expansive socio-technical efforts to establish enduring safety.

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Tadayoshi Kohno

Papers

Stateful Public-Key Cryptosystems: How to Encrypt with One 160-bit Exponentiation.

Understanding Privacy Attitudes and Concerns Towards Remote Communications During the COVID-19 Pandemic

Doctoring Direct-to-Consumer Genetic Tests with DNA Spike-Ins

Ethical Frameworks and Computer Security Trolley Problems: Foundations for Conversations

“There’s so much responsibility on users right now:” Expert Advice for Staying Safer From Hate and Harassment