The Password Control system plugin enforces password changes upon registered site users. The change can be enforced for the initial (first) connection only, and/or for periodic changing. Optionally the users can be redirected back to the home page when a password change is enforced. There is the ability to define 'exempt' users, i.e. users for whom the administrator does not want to enforce password changing. The password entered by the user is checked against the previous password to ensure that it is changed and that the user is not reusing the same password again, or just pressing the submit buttom without providing a new password.

Read more - Joomla! Extensions Directory - New Extensions