Actually I was wrong, we do already have this. You will need to write a ServletExtension
and then use thio.undertow.servlet.api.DeploymentInfo#setServletSessionConfig method. 
For an example of using a ServletExtension see
 From: "Stuart Douglas" <sdouglas(a)redhat.com>
 To: "Marc Boorshtein" <marc.boorshtein(a)tremolosecurity.com>
 Cc: undertow-dev(a)lists.jboss.org
 Sent: Tuesday, 15 October, 2013 1:30:29 PM
 Subject: Re: [undertow-dev] Customized Session Management?
 
 At the moment the answer is 'sort of'.
 
 This is controlled via the io.undertow.server.session.SessionConfig
 interface, however at the moment there is no ability to make this pluggable.
 If you file a JIRA I will add this.
 
 Stuart
 
 ----- Original Message -----
 > From: "Marc Boorshtein" <marc.boorshtein(a)tremolosecurity.com>
 > To: undertow-dev(a)lists.jboss.org
 > Sent: Monday, 14 October, 2013 5:07:54 PM
 > Subject: [undertow-dev] Customized Session Management?
 > 
 > Is it possible to dynamicly control session cookies (scope, domain, name,
 > value) on the fly based on the URL in a session handler or is the cookie
 > managed by the web server?
 > 
 > For instance if I want to generate a different cookie depending on the URL
 > with differeny keys, I generate a cookie based on the URL name that could
 > be
 > scoped at different levels. I could have a url calls
 > 
https://apps.company.com/ and decide I want to scope the cookie at
 > 
company.com . Is this something I can do pragmatically?
 > 
 > Thanks
 > 
 > --
 > Marc Boorshtein
 > CTO Tremolo Security
 > marc.boorshtein(a)tremolosecurity.com
 > 
 > 
 > _______________________________________________
 > undertow-dev mailing list
 > undertow-dev(a)lists.jboss.org
 > 
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