Find users with there privileges

conn / AS sysdba

SELECT grantee, privilege, admin_option
FROM sys.dba_sys_privs
WHERE (privilege LIKE '% ANY %'
OR privilege IN ('BECOME USER', 'UNLIMITED TABLESPACE')
OR admin_option = 'YES')
AND grantee NOT IN ('SYS', 'SYSTEM', 'OUTLN', 'AQ_ADMINISTRATOR_ROLE',
'DBA', 'EXP_FULL_DATABASE', 'IMP_FULL_DATABASE',
'OEM_MONITOR', 'CTXSYS', 'DBSNMP', 'IFSSYS',
'IFSSYS$CM', 'MDSYS', 'ORDPLUGINS', 'ORDSYS',
'TIMESERIES_DBA')