1. A method comprising: interacting with a web application during its execution to identify a web page exposed by the web application; statically analyzing the web page to identify a parameter within the web page that is constrained by a client-side validation measure and that is to be sent to the web application; determining a server-side validation measure to be applied to the parameter in view of the constraint placed upon the parameter by the client-side validation measure; statically analyzing the web application to identify a location within the web application where the parameter is input into the web application; determining whether the parameter is constrained by the server-side validation measure prior to the parameter being used in a security-sensitive operation; and identifying the parameter as a security vulnerability where the parameter is not constrained by the server-side validation measure prior to the parameter being used in the security-sensitive operation.