Biblio

Many web applications are vulnerable to Cross Site Scripting (XSS) attacks enabling attackers to steal sensitive information and commit frauds. Much research in this area have focused on detecting vulnerable web pages using static and dynamic program analysis. The best practice to prevent XSS vulnerabilities is to encode untrusted dynamic content. However, a common programming error is the use of a wrong type of encoder to sanitize untrusted data, leaving the application vulnerable. We propose a new approach that can automatically fix this common type of XSS vulnerability in many situations. This approach is integrated into the software maintenance life cycle through unit testing. Vulnerable codes are refactored to reflect the suggested encoder and then verified using an attack evaluating mechanism to find a proper repair. Evaluation of this approach has been conducted on an open source medical record application with over 200 web pages written in JSP.

Privilege Escalation is a common and serious type of security attack. Although experience shows that many applications are vulnerable to such attacks, attackers rarely succeed upon first trial. Their initial probing attempts often fail before a successful breach of access control is achieved. This paper presents an approach to automatically instrument application source code to report events of failed access attempts that may indicate privilege escalation attacks to a run time application protection mechanism. The focus of this paper is primarily on the problem of instrumenting web application source code to detect access control attack events. We evaluated false positives and negatives of our approach using two open source web applications.