Robert,

If you're using an "important" service (and I'll leave the definition of
important up to your organization) then you should always access that
application over SSL.  If you've accessed the application over SSL, then the
CAS ticket is not prone to a man-in-the-middle attack.  You could however
use the "I'm sitting at the computer and copied the url into another
browser" attack which really isn't an attack since its just you putting the
url into the browser.

If you access the service over standard HTTP, then everything is transmitted
and plain text and you do run the risk that someone could intercept the
ticket. We don't prevent you from using standard HTTP, but its not
recommended for "important" services such as ones with financial or student
data.

Regardless if someone was able to obtain the service ticket and utilize it
before the correct person did only that particular session for that
particular application would be compromised.  The SSO session as well as
other applications would be safe.

The CAS clients have no concept of associating a ticket with a session as
tickets don't exist when the session was created.

-Scott

-Scott Battaglia
PGP Public Key Id: 0x383733AA
LinkedIn: http://www.linkedin.com/in/scottbattaglia


On Mon, Aug 11, 2008 at 6:34 PM, Robert R <[EMAIL PROTECTED]> wrote:

> I have a question about whether or not a CAS ticket can be
> intercepted, and whether anyone thinks that is a problem.
>
> I am using the JavaClient 3.1.  If a user navigates to
> http://www.cas-protected-service.com/, the user is redirected to the
> CAS log in page, and asked to log in.  After the user is
> authenticated, there ultimately is a browser redirect to the following
> url: http://www.cas-protected-service.com/?ticket=ST-some-cas-ticket.
> Now - if I intercept this URL before this ticket is validated, and
> type it in on another browser with a different session, the new
> browser is validating this ticket and allowing me access to the page
> as the previously authenticated user.
>
> Is there something I am doing wrong, or is this the expected behavior?
>  Should the CAS client code check session cookies to make sure that
> the same client is validating the ticket?
>
> My web.xml exactly follows that of the example in the wiki.  I'm not
> doing anything strange.
>
> Thanks in advance.
>
> Robert
> _______________________________________________
> Yale CAS mailing list
> [email protected]
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>
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