The web application is extremely valuable in our everyday lives. Everyday lots of consumer access web applications to their daily desires such as; use ecommerce side for purchase products, banking application for money transfer, receives important information and email; communication with others people through the internet. Web application supports anyplace and anytime contacts consumer desire information for this reason; day by day its popularity is escalating for numerous users. Oppositely, a few attackers who’s we called ‘hacker’ who attacks with the preparation of creation an easy turnover to the general internet users. A considerable increase in the number of webbased attacks is prominence the significance of the techniques and methods for increasing the protection issues of the web applications. In this report discussed on some common client-side attacks against web applications and proposed a framework SWAF (Secure Web Application Framework) to ensure the security of web application in ASP.NET platform.