Need to have a sql query which is going to do cloning of Oracle user. As source I've user that has all necessary rights. I question if you'll be able to produce the same one, however with different username within the same database.

Briefly (from here)

select dbms_metadata.get_ddl('USER', '...') FROM DUAL;
SELECT DBMS_METADATA.GET_GRANTED_DDL('ROLE_GRANT','...') FROM DUAL;
SELECT DBMS_METADATA.GET_GRANTED_DDL('SYSTEM_GRANT','...') FROM DUAL;
SELECT DBMS_METADATA.GET_GRANTED_DDL('OBJECT_GRANT','...') FROM DUAL;
SELECT DBMS_METADATA.GET_granted_DDL(‘TABLESPACE_QUOTA’, ‘...’) FROM dual;

Then just replace the username using the brand new one you need to create.

just take a look only at that link

http://www.dba-oracle.com/t_cloning_oracle_user_id.htm