ORA-27369: job of type EXECUTABLE failed with exit code: Operation not permitted

When running external script by scheduler. The solution:

chown root $ORACLE_HOME/bin/extjob
chmod 4750 $ORACLE_HOME/bin/extjob

chown root $ORACLE_HOME/rdbms/admin/externaljob.ora
chmod 640 $ORACLE_HOME/rdbms/admin/externaljob.ora

chown root $ORACLE_HOME/bin/jssu
chmod 4750 $ORACLE_HOME/bin/jssu

Have a nice week!
Matheus.