Passing CDATA as custom SAML data using rules

hey, I’m performing and IDP-initiated-flow using AWS Cognito <> Auth0 <> SP
and would like to transfer CDATA for each specific user, dependent on the data it has received from cognito

I have Rule to support static data with mappings (see below)

And would like to pass CDATA which includes multiple attributes, something like that:

<saml:Attribute Name="ApplicationData" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:basic">
  <saml:AttributeValue>
  <![CDATA[<ApplicationData><UserData>
  <Data Name="FirstName"/>
  <Data Name="Phone"/>
  </UserData>
  <ClientData/>
  </ApplicationData>]]>
   </saml:AttributeValue>
</saml:Attribute>

my user comes with this data:

{
  
    "first_name": "x@gmail.com",
    "phone_number": "+12345678",
}

but not sure how can I transfer this data via rule?

{
  context.samlConfiguration.mapUnknownClaimsAsIs = true;
  context.samlConfiguration.mapIdentities = false;
  context.samlConfiguration.mappings = {
     "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier": "email",
     "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress":       "email",
    "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/user_id": "cognito:username",
   };
}

was thinking maybe something like that?
user.application_data = [user.phone_number, user.first_name];
then map it on the SamlConfiguration – but it won’t create multiple attributes.
thanks!