SQL> create table cust_bug_metadata(product_id number, component varchar2(50),sub_component varchar2(50), email varchar2(50));

Table created.

SQL> insert into cust_bug_metadata(product_id, component, sub_component, email) values(5757, 'extract', 'checkpoint','subhas@oracle.com');

1 row created.

SQL> insert into cust_bug_metadata(product_id, email) values(5757,'subhas@oracle.com');

1 row created.

SQL>
SQL>
SQL> create or replace procedure "SEND_BUG_EMAIL_DAILY"
  2  is
  3  component_value VARCHAR2(200);
  4  sub_component_value VARCHAR2(200);
  5  cursor mailCursor is select product_id from cust_bug_metadata;
  6  begin
  7  FOR m IN mailCursor LOOP
  8    select component,sub_component into component_value,sub_component_value from cust_bug_metadata where product_id = m.product_id;
  9  END LOOP;
 10  end;
 11  /

Procedure created.

SQL>
SQL>
SQL> exec SEND_BUG_EMAIL_DAILY;
BEGIN SEND_BUG_EMAIL_DAILY; END;

*
ERROR at line 1:
ORA-01422: exact fetch returns more than requested number of rows
ORA-06512: at "MCDONAC.SEND_BUG_EMAIL_DAILY", line 8
ORA-06512: at "MCDONAC.SEND_BUG_EMAIL_DAILY", line 8
ORA-06512: at line 1

--
-- if you want to cycle through all rows, then just add another cursor
--

SQL>
SQL> create or replace procedure "SEND_BUG_EMAIL_DAILY"
  2  is
  3  component_value VARCHAR2(200);
  4  sub_component_value VARCHAR2(200);
  5  cursor mailCursor is select product_id from cust_bug_metadata;
  6  begin
  7  FOR m IN mailCursor LOOP
  8    for inner in ( select component,sub_component into component_value,sub_component_value from cust_bug_metadata where product_id = m.product_id )
  9    loop
 10      do_something;
 11    end loop;
 12  END LOOP;
 13  end;
 14  /

Procedure created.

--
-- if you want to pick just one (arbitrary) row, you can add a predicate with rownum
--

SQL>
SQL> exec SEND_BUG_EMAIL_DAILY;

PL/SQL procedure successfully completed.

SQL>
SQL> create or replace procedure "SEND_BUG_EMAIL_DAILY"
  2  is
  3  component_value VARCHAR2(200);
  4  sub_component_value VARCHAR2(200);
  5  cursor mailCursor is select product_id from cust_bug_metadata;
  6  begin
  7  FOR m IN mailCursor LOOP
  8    select component,sub_component into component_value,sub_component_value from cust_bug_metadata where product_id = m.product_id and rownum = 1;
  9  END LOOP;
 10  end;
 11  /

Procedure created.

SQL>
SQL> exec SEND_BUG_EMAIL_DAILY;

PL/SQL procedure successfully completed.

--
-- if you know a particular criteria that will always give just one matching row (eg component = null in my test case), then use that
--

SQL>
SQL> create or replace procedure "SEND_BUG_EMAIL_DAILY"
  2  is
  3  component_value VARCHAR2(200);
  4  sub_component_value VARCHAR2(200);
  5  cursor mailCursor is select product_id from cust_bug_metadata;
  6  begin
  7  FOR m IN mailCursor LOOP
  8    select component,sub_component into component_value,sub_component_value from cust_bug_metadata where product_id = m.product_id and component is not null;
  9  END LOOP;
 10  end;
 11  /

Procedure created.

SQL>
SQL> exec SEND_BUG_EMAIL_DAILY;

PL/SQL procedure successfully completed.

SQL>
SQL>