Tomcat - Disable JSESSIONID in URL

I had a problem with a Java webapp that works within a Tomcat 6 container.

In fact when you block sites from setting any data inside your browser, Tomcat 6 rewrites the URL and add a JSESSIONID parameter in it. URL session IDs are sensible informations that shouldn't be transmitted via GET method for security concerns. It may also have a bad impact on SEO. Because sessionid is unique, multiple visits by the same search bot will return identical content with different URLs.

https://webapp.com/index.jsp;jsessionid=557206C363F1267A24AB769CA0DE4529.node01

Security is a major concern for our customers, and JSESSIONIDs appearing in the URLs freak them out (especially when they demonstrate that you can get a URL from the app, email it to someone else, and have that person magically bypass authentication and assume the role of the other user - of course as long as the session is still valid).

The thing is that URL-based session tracking is intended for web clients that do not support session cookies. Every browser worth mentioning supports these cookies, and almost nobody surfs with them disabled. Moreover we are comfortable saying that in order to use our application you need to have cookies enabled, so I'm making the assumption that if we disable the feature of putting JSESSIONID into the URLs cookie-based session setting/tracking will still function just as we expect it.

You have multiple solutions to disable URL rewriting :

1. 'disableURLRewriting' attribute

In Tomcat 6, you can disable URL rewriting by setting 'disableURLRewriting' attribute to true in your context.xml.

<?xml version='1.0' encoding='utf-8'?>
<Context docBase="PATH_TO_WEBAPP" path="/CONTEXT" disableURLRewriting="true">
</Context>

For this you have to make sure that attribute "cookies" in not set to false. This is the default.

Attribute cookies
Set to true if you want cookies to be used for session identifier communication if supported by the client (this is the default). Set to false if you want to disable the use of cookies for session identifier communication, and rely only on URL rewriting by the application.
Attribute disableURLRewriting
Set to true to disable support for using URL rewriting to track session IDs for clients of this Context. URL rewriting is an optional component of the servlet 2.5 specification but disabling URL rewriting will result in non-compliant behaviour since the specification requires that there must be a way to retain sessions if the client doesn't allow session cookies. If not specified, the specification compliant default value of false will be used.

2. "Servlet Filter"

You can use a servlet filter such as Tuckey which allow you to rewrite URLs before they get to your code.

3. Switch to Tomcat 7 !

The Servlet 3.0 standard gives you two ways to disable URL session rewriting. This works in Tomcat 7, Glassfish v3, and any other Servlet 3.0-compliant servlet container. First, you can add this to your web.xml webapp config:

<session-config>
     <tracking-mode>COOKIE</tracking-mode>
</session-config>

Or programmatically, you can use:

servletContext.setSessionTrackingModes(EnumSet.of(SessionTrackingMode.COOKIE));