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Using Dynamic Symbolic Execution to Generate Inputs in Search-based GUI Testing
No full textSearch-based testing has been successfully applied to generate complex sequences of events for graphical user interfaces (GUIs), but typically relies on simple heuristics or random values for data widgets like text boxes. This may greatly reduce the effectiveness of test generation for applications which expect specific input values to be entered in their GUI by users. Generating such specific input values is one of the virtues of dynamic symbolic execution (DSE), but DSE is less suitable to generate sequences of events. Therefore, this paper describes a hybrid approach that uses search-based testing to generate sequences of events, and DSE to build input data for text boxes. This is achieved by replacing standard widgets in a system under test with symbolic ones, allowing us to execute GUIs symbolically. In this paper, we demonstrate an extension of the search-based GUI testing tool EXSYST, which uses DSE to successfully increase the obtained code coverage on two case study applications
Vccfinder: Finding potential vulnerabilities in open-source projects to assist code audits
No full textRuntime Verification - 6th International Conference, RV 2015 Vienna, Austria, September 22-25, 2015. Proceedings
No full textDiffusion in Social and Information Networks: Research Problems, Probabilistic Models and Machine Learning Methods
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Cashing Out the Great Cannon? On Browser-Based DDoS Attacks and Economics
Get PDFThe Great Cannon DDoS attack has shown that HTML/JavaScript can be used to launch HTTP-based DoS attacks. In this paper, we identify options that could allow the implementation of the general idea of browser-based DDoS botnets and review ways how attackers can acquire bots (e.g., typosquatting and malicious ads). We then assess the DoS impact of browser features and show that at least three JavaScript-based techniques can orchestrate clients to send thousands of HTTP requests per second. Seeing the vats potential, we evaluate the economics of browser-based botnets and show that their cost are about as high as traditional DDoS botnets—while giving far less flexibility in terms of attack features and control over the bots. Finally, we discuss victim- and browser-side countermeasures
jÄk: Using Dynamic Analysis to Crawl and Test Modern Web Applications
Get PDFWeb application scanners are popular tools to perform black box testing and are widely used to discover bugs in websites. For them to work effectively, they either rely on a set of URLs that they can test, or use their own implementation of a crawler that discovers new parts of a web application. Traditional crawlers would extract new URLs by parsing HTML documents and applying static regular expressions. While this approach can extract URLs in classic web applications, it fails to explore large parts of modern JavaScript-based applications. In this paper, we present a novel technique to explore web applications based on the dynamic analysis of the client-side JavaScript program. We use dynamic analysis to hook JavaScript APIs, which enables us to detect the registration of events, the use of network communication APIs, and dynamically-generated URLs or user forms. We then propose to use a navigation graph to perform further crawling. Based on this new crawling technique, we present j¨Ak, a web application scanner. We compare jÄk against four existing web-application scanners on 13 web applications. The experiments show that our approach can explore a surface of the web applications that is 86% larger than with existing approaches