Semantic security against web application attacks

Semantic security against web application attacks

Abstract— Semantic security against web application attacks. Timeout mechanisms are a useful feature for web applications. However, these mechanisms need to be used with care because, if used as-is, they are vulnerable to timing attacks. This paper focuses on internal timing attacks, a particularly dangerous class of timing attacks, where the attacker needs no access to a clock. In the context of client-side web application security, we present JavaScript-based exploits against the timeout mechanism of the DOM (document object model), < Final Year Projects > supported by the modern browsers. Our experimental findings reveal rather liberal choices for the timeout semantics by different browsers and motivate the need for a general security solution. We propose a foundation for such a solution in the form of a runtime monitor. We illustrate for a simple language that, while being more permissive than a typical static analysis, the monitor enforces termination-insensitive noninterference.