Re: Unable to impersonate another user although having its cookie

[Guillermo Caminer <flaco.webappsec () gmail com>]

Since HTTP is a stateless protocol, the only way the server can relate a request to a user is to
maintain a session: in your case, with a cookie. But of course, it is possible to use ANY data in
the HTTP request to do this association (data which you CAN control, unless there is some encrypted
parameters) and maybe (unfortunately for you) some data you can not (like origin IP address, SSL ID).

So go ahead and play with the parameters you can control and try to reproduce the stolen session
request.

One more thing: are you considering the application business logic? Some applications require the
actions to be taken in a certain order. Ex: opA, opB then opC. Maybe you're "jumping" actions (going
from opA straight to opC) and that's why you're getting disconnected. Always consider the
application business logic.

By the way: you do not need to use different browsers to test sessions. You can run two instances of
firefox with the 'no-remote' command line option. This way you can have to different instances which
do not share cookies (you can also have two different firefox profiles running). This way you don't
have to copy the User-Agent header that IE is sending to the server.

Guillermo Caminer

> > > owns each cookie.
>
> The server only knows what the client told it, which is all contained within the request.  It is possible for the 
> server to attempt to validate the IP address and/or some HTTP headers, such as user-agent and referer. Validating the 
> headers is somewhat uncommon because they are so easily manipulated. I wouldn't go there first in terms of 
> troubleshooting, but that could be it. If we're talking SSL, perhaps the SSL session id is somehow tied to the 
> application session identifier?
>
> Did the actual request with the appended cookie value fail?  What can happen is that the browser fetches other 
> resources (images, etc) that don't contain the cookie you manually added.  This results in a failure (possibly a 
> redirect), obscuring the fact that your "session hijacking" actually worked. I know I've missed this on occasion;-)
>
> > > Is this possible? Is it the normal operation in sessions in CakePHP?
>
> See "S I" response.  Cake has validating the user agent header as a config option it seems.
>
>
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