How to prevent a user from changing the password?

In situations where many users log on to the database with a single account, it is very important to prevent a user from changing the password. The following article provides code that enables a DBA to prevent certain users to change their password. The following function can be used to prevent a user from changing their password. This function requires use of a USER PROFILE to activate the function. This script MUST be run while connected as the SYS user.

Create the function


Connect as sysdba

set term on
set echo on

CREATE OR REPLACE FUNCTION verify_function_fix_pwd (
    username      VARCHAR2
  , password      VARCHAR2
  , old_password  VARCHAR2) RETURN boolean IS
BEGIN
    raise_application_error(-20009, 'ERROR: Password cannot be changed');
END;
/

show errors

Create profile

The following profile will contain a limit PASSWORD_VERIFY_FUNCTION associated to the previously created function. This profile must be assigned to all users who are NOT allowed to change their password. 

DROP PROFILE fixpwd CASCADE;
CREATE PROFILE fixpwd LIMIT PASSWORD_VERIFY_FUNCTION verify_function_fix_pwd;Example Run 
DROP USER test_pwd;
CREATE USER test_pwd IDENTIFIED BY test_pwd
  DEFAULT TABLESPACE users
  TEMPORARY TABLESPACE temp
  ACCOUNT UNLOCK;
GRANT connect TO test_pwd;
ALTER USER test_pwd PROFILE fixpwd;

Connect to user test_pwd


SQL> connect test_pwd/test_pwd
Connected.

Try to change the password


SQL> ALTER USER test_pwd IDENTIFIED BY test REPLACE test_pwd;
ALTER USER test_pwd IDENTIFIED BY test REPLACE test_pwd
*
ERROR at line 1:
ORA-28003: password verification for the specified password failed
ORA-20009: ERROR: Password cannot be changed

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