Adpatch Worker Fails with "ORA-01031: insufficient privileges"

While Applying Patch on Customer environment, adpatch failed with error

Worker log has the below error.
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GRANT select on DBA_USERS_WITH_DEFPWD to em_oam_monitor_role

AD Worker error:
The following ORACLE error:

ORA-01031: insufficient privileges


occurred while executing the SQL statement:

GRANT select on DBA_USERS_WITH_DEFPWD to em_oam_monitor_role

Error occurred in file

/test12/applmgr/1200/ad/12.0.0/patch/115/sql/ademusr.sql

with arguments '&systempwd &un_fnd &pw_fnd &un_apps &pw_apps'.

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Solution
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1.Login to oracle database server as oracle user

2. Connect to sqlplus as sysdba and run the failed sql statement
sqlplus / as sysdba

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> GRANT select on DBA_USERS_WITH_DEFPWD to em_oam_monitor_role
  2  ;

Grant succeeded.

SQL>


3. Use adctrl to skip the failed worker (Option 8) and continue with Patching