The paper is a must-read for anyone trying to understand scope design of APIs as well as those that would design registries or trust frameworks to guide users that are considering signing up for an new app or web service.
https://arxiv.org/abs/1608.05661arXiv:1608.05661 (*cross-listing*)Date: Thu, 18 Aug 2016 07:36:11 GMT (2469kb,D)Title: The Curious Case of the PDF Converter that Likes Mozart: Dissecting and Mitigating the Privacy Risk of Personal Cloud AppsAuthors: Hamza Harkous, Rameez Rahman, Bojan Karlas, Karl AbererCategories: cs.CY cs.HCJournal-ref: Proceedings on Privacy Enhancing Technologies. Volume 2016, Issue 4, Pages 123-143, ISSN (Online) 2299-0984DOI: 10.1515/popets-2016-0032\\ Third party apps that work on top of personal cloud services such as GoogleDrive and Dropbox, require access to the user's data in order to provide somefunctionality. Through detailed analysis of a hundred popular Google Drive appsfrom Google's Chrome store, we discover that the existing permission model isquite often misused: around two thirds of analyzed apps are over-privileged,i.e., they access more data than is needed for them to function. In this work,we analyze three different permission models that aim to discourage users frominstalling over-privileged apps. In experiments with 210 real users, wediscover that the most successful permission model is our novel ensemble methodthat we call Far-reaching Insights. Far-reaching Insights inform the usersabout the data-driven insights that apps can make about them (e.g., theirtopics of interest, collaboration and activity patterns etc.) Thus, they seekto bridge the gap between what third parties can actually know about users andusers perception of their privacy leakage. The efficacy of Far-reachingInsights in bridging this gap is demonstrated by our results, as Far-reachingInsights prove to be, on average, twice as effective as the current model indiscouraging users from installing over-privileged apps. In an effort forpromoting general privacy awareness, we deploy a publicly available privacyoriented app store that uses Far-reaching Insights. Based on the knowledgeextracted from data of the store's users (over 115 gigabytes of Google Drivedata from 1440 users with 662 installed apps), we also delineate the ecosystemfor third-party cloud apps from the standpoint of developers and cloudproviders. Finally, we present several general recommendations that can guideother future works in the area of privacy for the cloud.--