On 16/11/2012 10:01, André Warnier wrote: > Vijaya Kumar wrote: >> Hi, I work on a web application that is vulnerable to CSRF(Cross Site >> Request Forgery) attack. Tomcat 7 has a CSRF prevention filter. I went >> through the description to configure this filter. This filter expects >> that we call HttpServletResponse#encodeRedirectURL(String) or >> HttpServletResponse#encodeURL(String). I see that in my application we >> don't use the above mentioned methods. Can you please let me know >> whether there is any other way of using this filter without making >> calls to encodeURL() or encodeRedirectURL()? >> To be precise, I am looking for a way to incorporate CSRF Filter in an >> already existing application that doesn't use >> HttpServletResponse#encodeRedirectURL(String) or >> HttpServletResponse#encodeURL(String). >> Any help in this regard is appreciated. > > Hi. > I am a bit of a novice in this area, but as far as I understand what a > CSRF attack is > (http://en.wikipedia.org/wiki/Cross-site_request_forgery), and what this > filter does, it seems to me at least that if your are not using > HttpServletResponse#encodeRedirectURL(String) or > HttpServletResponse#encodeURL(String) in your application, then this > filter would be unnecessary, and would not help anyway.
Wrong. In order for the CSRF prevention filter to work, an application must run all URLs through encodeRedirectURL() or encodeURL(). If applications don't do this, the filter can't add the nonce to the URL that is used to provide the CSRF protection. Note: That filter is very generic and works for simple applications (e.g. Tomcat's HTML Manager app) but is likely to be quite tricky to set up for complex applications. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
