The growing market of the mobile application is overtaking the web application. Mobile application development environment is open source, which attracts new inexperienced developers to gain hands on experience with application development. However, the security of data and vulnerable coding practice is an issue. Among all mobile Operating systems such as, iOS (by Apple), Android (by Google) and Blackberry (RIM), Android dominates the market. The majority of malicious mobile attacks take advantage of vulnerabilities in mobile applications, such as sensitive data leakage via the inadvertent or side channel, unsecured sensitive data storage, data transition and many others. Most of these vulnerabilities can be detected during mobile application analysis phase. In this paper, we explore vulnerability detection for static and dynamic analysis tools. We also suggest limitations of the tools and future directions such as the development of new plugins.
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OS-level Side Channels without Procfs: Exploring Cross-App Information Leakage on iOS
It has been demonstrated in numerous previous studies that Android and its underlying Linux operating systems do not properly isolate mobile apps to prevent cross-app side- channel attacks. Cross-app information leakage enables malicious Android apps to infer sensitive user data (e.g., passwords), or private user information (e.g., identity or location) without requiring specific permissions. Nevertheless, no prior work has ever studied these side-channel attacks on iOS-based mobile devices. One reason is that iOS does not implement procfs— the most popular side-channel attack vector; hence the previously known attacks are not feasible.
In this paper, we present the first study of OS-level side-channel attacks on iOS. Specifically, we identified several new side-channel attack vectors (i.e., iOS APIs that enable cross-app information leakage); developed machine learning frameworks (i.e., classification and pattern matching) that combine multiple attack vectors to improve the accuracy of the inference attacks; demonstrated three categories of attacks that exploit these vectors and frameworks to exfiltrate sensitive user information. We have reported our findings to Apple and proposed mitigations to the attacks. Apple has incorporated some of our suggested countermeasures into iOS 11 and MacOS High Sierra 10.13 and later versions.
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- PAR ID:
- 10057424
- Date Published:
- Journal Name:
- Proceedings of the Symposium on Network and Distributed System Security
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.14722/ndss.2018.23260
