Oracle Database Discussions

I read the view dba_tab_roles with a user having the select_catalog_role.
dba_tab_roles contains a field default_role.
If this fields contains the value YES, sometimes the role has to be added to the user as default role with the command
alter user xxx default role r1,r2,..;

The table sys.user$ contains a field defrole.
Reading this field I can decide if the alter user xxx default role .... command is required or not.
Unfortunately I have to connect as dba to see the table sys.user$, with a user having only the select_catalog_role I'm not able to access this table.
Where can I find this info using a userid having only the select_catalog_role?

Thanks
Tauber Johann