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Uncovering Privacy and Security Issues in Android Apps at Scale Through Comprehensive Dynamic Analysis
No full textThe widespread adoption of the Android operating system has brought significant convenience to users globally. However, this prevalence has also exposed users to new forms of privacy and security threats originating from the apps they use. Android apps often collect and process sensitive user sensitive information without their user's explicit awareness or consent, using sophisticated techniques that traditional security measures fail to detect.
This thesis addresses critical gaps in mobile privacy and security by exploring three under-researched areas: (i) detection of privacy leaks via non-standard communication, (ii) identification and attribution of TLS certificate validation failures, and (iii) privacy risks from out-of-sight app operations.
First, we developed ThirdEye, a dynamic analysis tool designed to detect privacy leaks by focusing on the use of custom encryption across both HTTP/S and non-HTTP protocols, as well as covert channels via shared storage media. Utilizing ThirdEye, we analyzed 12,598 popular Android apps and discovered that 2,887 apps employed custom encryption for network transmission and storage. Among these, 2,465 apps transmitted device information that could be used to fingerprint users. Additionally, 299 apps transmitted insecurely encrypted content, and several utilized vulnerable cryptographic keys and weak algorithms such as RC4 and DES.
Second, we introduced Marvin, an automated dynamic analysis tool designed to identify TLS certificate validation failures, including the phenomenon we term validation hijacking. Marvin exercises app states to maximize coverage of potential TLS connections, traces real-time code execution related to TLS validation, and captures network traffic using a man-in-the-middle proxy with intentionally invalid certificates. Our analysis showed that a significant number of apps exhibited insecure TLS certificate validation, with validation hijacking prevalent due to insecure overrides in third-party libraries like OkHttp, often without developers’ awareness.
Third, we developed BackChecker, a novel dynamic analysis tool that detects and attributes data leakage occurring during out-of-sight app operations across multiple apps simultaneously. BackChecker systematically triggers and monitors Android background processes, including services and job schedulers, to identify privacy leaks when the app is not actively in use. Our large-scale empirical study of 15,456 popular Android apps revealed that 13,068 apps established network connections while not visible, 7,534 continued activity regardless of app state, and 10,524 transmitted sensitive information during out-of-sight operations. Additionally, we uncovered undocumented and inconsistent behaviors in Android that facilitate background execution, highlighting significant issues in platform policies.
By addressing these challenges, this thesis contributes to the development of more robust privacy and security measures in the Android ecosystem. Our tools provide advanced capabilities for detecting such sophisticated threats. The findings offer valuable insights into systemic vulnerabilities in modern mobile apps, emphasizing the need for enhanced detection mechanisms and stricter enforcement of security practices
Reflexively Revisiting Three Participatory Cellphilm Archives.
No full textWhat happens to cellphilm archives produced in participatory visual research projects after the projects end? This chapter reflexively revisits three YouTube-based cellphilm archives one from Hong Kong (2015) and two from New Brunswick, Canada (2020, 2021) and suggests that although theorized as participatory, the three examples of archives explored in the chapter don’t quite do what I had set out for them to do. And yet, they offer something for participatory researchers interested in archiving and exhibition over time to think about in relation to the curatorial function of the participatory researcher, and how the archive remains and might be audienced beyond the scope of the project. These are important considerations as we think about what to do with the cellphilm archives that emerge from a project over longer periods of time
Plan S and Open Access (OA) in Quebec: What does the revised FRQ OA policy mean for researchers?
Get PDFObjective: Our article examines the effects of Quebec’s provincial funding agency (FRQ)’s revised 2022 OA policy on researchers. Following FRQ’s participation as a cOAlition S funding agency, which involves endorsing Plan S principles, we provide an overview of the OA options for researchers. We examine these options under the FRQ 2019 and FRQ 2022 policy years, account for the effect of transformative agreements (TA) on OA publishing options, as well as the financial implications for researchers under the revised policy.
Methods: The researchers extracted a list of FRQ-funded publications from years 2020 to 2022 using the DOI registration agency Crossref. Using this sample set, we, the researchers, quantitatively analyzed OA options under the previous policy and the revised one, comparing the two. To determine the effect of transformative agreements (TAs)s, we reviewed current agreements offered through Canada’s national licensing agency Canadian Research Knowledge Network (CRKN).
Results: We found that the self-archiving method for open access (OA) is reduced under the revised 2022 policy. Our results lead us to anticipate the pressure felt by authors who will be required to pay article processing charges (APCs) to meet grant requirements.
Conclusion: The current publishing patterns of FRQ-funded researchers are primarily concentrated in hybrid journals not covered by transformative agreements. As such, researchers will face additional financial costs should these publishing patterns continue. Concerted efforts among all stakeholders (researchers, universities, libraries, and funders) are needed to sustainably transition to immediate OA
“How in the hell do you get home?”: Listening to the particular in “Prince George, Finally”
Get PDFWhile inputting metadata as part of my RA work for Simon Fraser University’s SpokenWeb team, there was one tape that I kept coming back to. The tape is a recording of poet Brian Fawcett reading and being interviewed for the radio program Mountain Pass. After returning to this recording again and again, I decided to visit SFU’s Special Collections and Rare Books to read the manuscript of a poem featured on the recording in person. The physical poem, however, carried a sense of dissonance from the recording. Reading it challenged my understanding of what the poem was and disrupted the sense of familiarity I had developed through listening. This post is an attempt to work through some of these differences and question what I expected to find in the poem in the first place
Assessing land-use legacy effects on soil physico-chemical properties and earthworm biodiversity in urban parks
Get PDFHuman land-use alters soil properties and biodiversity differently depending on the intensity and type of use, often resulting in persistent temporal effects known as legacy effects. Cities are expected to be rich in legacy effects due to their development histories and complex socio-ecological landscapes. However, few urban ecological studies consider the role of history in shaping contemporary patterns. Therefore, we asked: do soil properties and biodiversity of our present-day urban greenspaces differ due to varied historical land-use? We surveyed 25 urban parks across the island of Montreal, Quebec, Canada with three former land-uses: forested (low intensity), agricultural (medium intensity), and industrial (high intensity). We measured soil bulk density, heavy metal concentrations, and carbon and nitrogen stocks, as well as earthworm abundance, biomass, species richness, and community composition. Most studied soil properties did not differ across historical land-uses. All properties except for heavy metal concentrations significantly increased with age, implying a legacy effect of recovery from disturbance and management post park establishment. Earthworm distribution was highest in forested sites whereas earthworm biodiversity was lower in previously agricultural sites. These findings suggest that aspects of soils in our urban greenspaces are minimally susceptible to legacy effects of historical human land-use. This demonstrates a certain effectiveness in developing municipal parks on a variety of past land-uses. This could allow for a focusing on current management choices and decisions which may have a greater influence on park ecosystem functioning
Eliminating White Supremacist culture as well as scientific and academic racism in translation studies (and beyond) by using Sacred, Ancestral, and emergent Afro-Indigenous, anti- and de-colonial languages and practices
Get PDFThis thesis introduces a groundbreaking step-by-step framework to translate Afro-Indigenous and other Indigenous languages anti-colonially without any racist and White Supremacist scientific biases (contrary to the established institutional norm and practice). It shows how to avoid whitewashing such translations and how to properly Indigenize the text as needed. This framework imparts tools to help properly retranslate corrupt source texts (i.e. original source texts that are so whitewashed that they erase Haitian's core Afro-Indigeneity). This thesis uses Frankétienne's seminal Masterpiece Dezafi as a model of what true Haitian looks like and of what a bias-free source and target texts need to look like post-translation to be scientifically accurate. As such, a breakdown of some of the top most common mistakes is introduced what is specific to translations from and into Haitian. Overarchingly, this thesis debunks historically entrenched racist and White Supremacist myths pervasive in Translation Studies (and beyond) about Haitian and it scientifically disproves its imposed status as a so-called "Creole" language and instead establishes it as a legitimate fully fledged Afro-Indigenous language that is anti-colonially African and Indigenous rather than reductively or necessarily "French"
Harnessing Digital and Droplet Microfluidics to Advance Synthetic Biology
No full textAs we strive to engineer biological systems, we must first understand the fundamental parts. This requires
us to examine vast arrays of genetic variation, potentially ranging from hundreds to millions of subtle differences
for each system, highlighting a need for high-throughput automation. Such automation is essential,
not only for facilitating rapid development through continuous cycles of design, construction, and testing,
but ultimately to integrate with machine learning algorithms: a synergy that will bypass the sluggish tempo
of natural evolution and unleash a massive wave of synthetic biology.
In addressing automation needs, this thesis delves into the development and implementation of droplet
and digital microfluidics technologies. These innovations mark a significant breakthrough in automation
while also introduce added benefits of miniaturization. Additionally, the use of optogenetics to control gene
expression presents an opportunity to interface biology with the highly established field of digital control
systems.
The thesis is structured into distinct chapters, each contributing uniquely to the field. The foreword acts
as a guide for the thesis. The first chapter offers a thorough exploration of droplet microfluidics in synthetic
biology, highlighting its critical role and projecting its contribution to the forthcoming bio-revolution.
This is followed by three primary research studies. The first study details innovative techniques in digital
microfluidics for DNA assembly and transformation. The second study focuses on developing optogenetic
control of gene expression, using a model-based design strategy. The third study discusses the integration
of optogenetic systems within a droplet-in-channel microfluidic environment, showcasing the potential for
future applications in synthetic biology and beyond. The concluding chapter serves as a reflection and ties
these works to a greater synthetic biology vision.
Through these studies, this thesis not only addresses the immediate needs of automation in synthetic biology
but also establishes a foundation for future research, highlighting the need for microfluidic technologies
Adaptive Priors in Probabilistic Topic Models for Bursty Discovery in Textual Data
Get PDFIn the field of natural language processing, topic modeling plays an important role in detecting latent topics in large amounts of text. Models that use traditional methods of representation, however, often fail to capture the 'burstiness' characteristic of natural language - the tendency for previously occurring words to recur within the same document. In order to address this limitation, we introduce two innovative topic modeling frameworks: the Generalized Dirichlet Compound Multinomial Latent Dirichlet Allocation (GDCMLDA) and the Beta-Liouville Dirichlet Compound Multinomial Latent Dirichlet Allocation (BLDCMLDA). Using Dirichlet Compound Multinomial distribution together with Generalized Dirichlet and Beta-Liouville distributions, both frameworks integrate advanced distribution methods. By integrating these concepts, it is possible to model the burstiness phenomenon while maintaining a variety of topic proportion patterns that can be varied and flexible. As a result of our comprehensive evaluations across multiple benchmark text datasets, we conclude that GDCMLDA and BLDCMLDA are superior to existing models. The evidence for this is found in the improved performance metrics, including the scores for perplexity and coherence. Our results confirm that the proposed models are able to capture the complexities of word usage dynamics, thus contributing to a significant advancement in topic modeling
Behavioural Consultation in Preschool Settings for Children with Behavioural Difficulties: Two Case Studies
Get PDFApproximately 5%-20% of preschool children exhibit significant challenging behaviours within the classroom, stemming from underlying behavioural or emotional difficulties (Campbell, 1995; Charach et al., 2020). However, most early childhood educators do not feel supported or equipped to handle these challenging behaviours due to a lack of training and resources, low confidence, and a growing pressure to perform (Arnold et al., 2006; Moore et al., 2017). This qualitative research study investigated the impact of implementing Behavioural Consultation (Kratochwill & Bergan, 1990) in preschool classrooms to support educators who intervened with children with behaviour challenges. Collaborative meetings with educators over the course of 10 weeks were implemented to investigate changes in educators’ knowledge of children’s behavioural needs, educators’ knowledge of appropriate strategies, educators’ self-efficacy, and children’s display of challenging behaviours. Findings from pre- and post- intervention interviews, questionnaires, and child observations were analysed. Thematic coding revealed that preschool educators’ experiences with the consultation process partially improved their self-efficacy when they used more developmentally appropriate behaviour strategies that positively impacted the children’s behaviours. Educators’ use of positive behavioural strategies matched the children’s developmental and individual needs and served to improve the educators’ perceptions of the children. These findings have implications for designing professional development programs in preschool settings to support educators who intervene with children with behavioural difficulties
Information Revelation in Second Price Auctions
Get PDFIn this paper, I model a second price auction with an informed and an uninformed bidder and find the optimal information revealing strategy followed by the informed bidder at equilibrium. The informed bidder knows the state of the world with certainty, but the uninformed bidder does not know it. The informed buyer can commit to a strategy to reveal information to the uninformed buyer. The uninformed buyer then updates his belief about the state of the world based on the information revealed. I characterize the information revealing strategy that maximizes the expected payoff of the informed bidder. The strategy depends upon the state of the world, valuation of the informed bidder, and the distribution of valuations of the uninformed bidder for the object in the auction. The social planner's optimal decision would be to reveal complete information to remove the inefficiencies in the auction due to information asymmetry