Mobile apps are increasingly used in daily activities. Most apps require Internet connectivity to be fully exploited. Despite the fact that global access to the Internet has improved over the years, there are still complex connectivity scenarios, including situations with zero/unreliable connectivity. In such scenarios, improper handling of Eventual Connectivity Issues may cause bugs and crashes that worsen the user experience. Even though these issues have been studied in the literature, no automatic detection techniques are available. To address the mentioned gap, we have created the open source CONAN tool. CONAN can statically detect 16 types of Eventual Connectivity Issues within Android apps; it works at the source code level and alerts developers of any connectivity issue, highlighting them directly in the IDE or generating a report explaining the detected errors. In this paper, we present the technical aspects and a video of our tool, which are publicly available at https://tinyurl.com/CONAN-lint.

Android is the most popular mobile operating system in the world, running on more than 70% of mobile devices. This implies a gigantic and very competitive market for Android apps. Being successful in such a market is far from trivial and requires, besides the tackling of a problem or need felt by a vast audience, the development of high-quality apps. As recently showed in the literature, connectivity issues (e.g., mishandling of zero/unreliable Internet connection) can result in bugs and/or crashes, negatively affecting the app's user experience. While these issues have been studied in the literature, there are no techniques able to automatically detect and report them to developers. We present CONAN, a tool able to detect statically 16 types of connectivity issues affecting Android apps. We assessed the ability of CONAN to precisely identify these issues in a set of 44 open source apps, observing an average precision of 80%. Then, we studied the relevance of these issues for developers by (i) conducting interviews with six practitioners working with commercial Android apps, and (ii) submitting 84 issue reports for 27 open source apps. Our results show that several of the identified connectivity issues are considered as relevant by practitioners in specific contexts, in which connectivity is considered a first-class feature.

Android is nowadays the most popular operating system in the world, not only in the realm of mobile devices, but also when considering desktop and laptop computers. Such a popularity makes it an attractive target for security attacks, also due to the sensitive information often manipulated by mobile apps. The latter are going through a transition in which the Android ecosystem is moving from the usage of Java as the official language for developing apps, to the adoption of Kotlin as the first choice supported by Google. While previous studies have partially studied security weaknesses affecting Java Android apps, there is no comprehensive empirical investigation studying software security weaknesses affecting Android apps considering (and comparing) the two main languages used for their development, namely Java and Kotlin. We present an empirical study in which we: (i) manually analyze 681 commits including security weaknesses fixed by developers in Java and Kotlin apps, with the goal of defining a taxonomy highlighting the types of software security weaknesses affecting Java and Kotlin Android apps; (ii) survey 43 Android developers to validate and complement our taxonomy. Based on our findings, we propose a list of future actions that could be performed by researchers and practitioners to improve the security of Android apps.

Deep learning (DL) techniques are on the rise in the software engineering research community. More and more approaches have been developed on top of DL models, also due to the unprecedented amount of software-related data that can be used to train these models. One of the recent applications of DL in the software engineering domain concerns the automatic detection of software vulnerabilities. While several DL models have been developed to approach this problem, there is still limited empirical evidence concerning their actual effectiveness especially when compared with shallow machine learning techniques. In this paper, we partially fill this gap by presenting a large-scale empirical study using three vulnerability datasets and five different source code representations (i.e., the format in which the code is provided to the classifiers to assess whether it is vulnerable or not) to compare the effectiveness of two widely used DL-based models and of one shallow machine learning model in (i) classifying code functions as vulnerable or non-vulnerable (i.e., binary classification), and (ii) classifying code functions based on the specific type of vulnerability they contain (or "clean", if no vulnerability is there). As a baseline we include in our study the AutoML utility provided by the Google Cloud Platform. Our results show that the experimented models are still far from ensuring reliable vulnerability detection, and that a shallow learning classifier represents a competitive baseline for the newest DL-based models.

Mobile developers constantly have to deal with users pressure for continuous delivery of apps while keeping quality attributes such as confidentiality and data integrity. To better support developers in testing security vulnerabilities during evolution and maintenance of mobile apps, in this demo we present a novel tool, OPIA, for on-device security testing. OPIA allows developers/testers to (i) conduct SQL-injection attacks and collect logs to identify leaks of sensitive information through record-and-replay testing, and (ii) extract data stored in local databases and shared preferences to identify sensitive information that is not properly encrypted, anonymized. OPIA is publicly available at GitHub.

In the context of smart homes, owners with no technical expertise will need to manage users and devices with various features to define who is allowed to use, or not, each smart device. To help owners perform this task, we designed a management framework that uses real life attributes and an attribute-based access control model (ABAC) to define access control policies. We built a prototype of the framework and found that users easily understand and use it to define access control policies for smart homes.