Gather system stats on EXADATA X4-2 throws an ORA-20001,ORA-06512

After a recent patch deployment on Exadata X4-2 system, the following error encountered whilst gathering system stats with Exadata mode (dbms_stats.gather_system_stats('EXADATA')):

SQL> exec dbms_stats.gather_system_stats('EXADATA');
BEGIN dbms_stats.gather_system_stats('EXADATA'); END;

*
ERROR at line 1:
ORA-20001: Invalid or inconsistent input values
ORA-06512: at "SYS.DBMS_STATS", line 27155
ORA-06512: at line 1

It appears to be a BUG, and the following workaround should resolve the issue:

(1) As SYS user execute the scripts below:

SQL> @?/rdbms/admin/dbmsstat.sql
SQL> @?/rdbms/admin/prvtstas.plb
SQL> @?/rdbms/admin/prvtstat.plb
SQL> @?/rdbms/admin/prvtstai.plb

(2) Then, re-run your DBMS_STATS call:

exec dbms_stats.gather_system_stats('EXADATA');

Indeed this worked for us and hope this would work for you as well.