Biblio

This paper presents the design and implementation of an information flow tracking framework based on code rewrite to prevent sensitive information leaks in browsers, combining the ideas of taint and information flow analysis. Our system has two main processes. First, it abstracts the semantic of JavaScript code and converts it to a general form of intermediate representation on the basis of JavaScript abstract syntax tree. Second, the abstract intermediate representation is implemented as a special taint engine to analyze tainted information flow. Our approach can ensure fine-grained isolation for both confidentiality and integrity of information. We have implemented a proof-of-concept prototype, named JSTFlow, and have deployed it as a browser proxy to rewrite web applications at runtime. The experiment results show that JSTFlow can guarantee the security of sensitive data and detect XSS attacks with about 3x performance overhead. Because it does not involve any modifications to the target system, our system is readily deployable in practice.
 

Testing for security related issues is an important task of growing interest due to the vast amount of applications and services available over the internet. In practice testing for security often is performed manually with the consequences of higher costs, and no integration of security testing with today's agile software development processes. In order to bring security testing into practice, many different approaches have been suggested including fuzz testing and model-based testing approaches. Most of these approaches rely on models of the system or the application domain. In this paper we suggest to formalize attack patterns from which test cases can be generated and even executed automatically. Hence, testing for known attacks can be easily integrated into software development processes where automated testing, e.g., for daily builds, is a requirement. The approach makes use of UML state charts. Besides discussing the approach, we illustrate the approach using a case study.

CSRFGuard is a tool running on the Java EE platform to defend Cross-Site Request Forgery (CSRF) attacks, but there are some shortcomings: scripts should be inserted manually, dynamically created requests cannot be effectively handled as well as defense can be bypassed through Cross-Site Scripting (XSS). Corresponding improvements were made according to the shortcomings. The Servlet filter was used to intercept responses, and responses of pages' source codes were stored by a custom response wrapper class to add script tags, so that scripts were automatically inserted. JavaScript event delegation mechanism was used to bind forms with onfocus and onsubmit events, then dynamically created requests were effectively handled. Token dynamically added through event triggered effectively prevented defense bypassed through XSS. The experimental results show that improved CSRFGuard can be effective to defend CSRF attacks.
 

One of the major threats against web applications is Cross-Site Scripting (XSS). The final target of XSS attacks is the client running a particular web browser. During this last decade, several competing web browsers (IE, Netscape, Chrome, Firefox) have evolved to support new features. In this paper, we explore whether the evolution of web browsers is done using systematic security regression testing. Beginning with an analysis of their current exposure degree to XSS, we extend the empirical study to a decade of most popular web browser versions. We use XSS attack vectors as unit test cases and we propose a new method supported by a tool to address this XSS vector testing issue. The analysis on a decade releases of most popular web browsers including mobile ones shows an urgent need of XSS regression testing. We advocate the use of a shared security testing benchmark as a good practice and propose a first set of publicly available XSS vectors as a basis to ensure that security is not sacrificed when a new version is delivered.

The inappropriate use of features intended to improve usability and interactivity of web applications has resulted in the emergence of various threats, including Cross-Site Scripting(XSS) attacks. In this work, we developed ETSS Detector, a generic and modular web vulnerability scanner that automatically analyzes web applications to find XSS vulnerabilities. ETSS Detector is able to identify and analyze all data entry points of the application and generate specific code injection tests for each one. The results shows that the correct filling of the input fields with only valid information ensures a better effectiveness of the tests, increasing the detection rate of XSS attacks.
 

Currently, dependence on web applications is increasing rapidly for social communication, health services, financial transactions and many other purposes. Unfortunately, the presence of cross-site scripting vulnerabilities in these applications allows malicious user to steals sensitive information, install malware, and performs various malicious operations. Researchers proposed various approaches and developed tools to detect XSS vulnerability from source code of web applications. However, existing approaches and tools are not free from false positive and false negative results. In this paper, we propose a taint analysis and defensive programming based HTML context-sensitive approach for precise detection of XSS vulnerability from source code of PHP web applications. It also provides automatic suggestions to improve the vulnerable source code. Preliminary experiments and results on test subjects show that proposed approach is more efficient than existing ones.