Using VBO to change users passwords
Userplus has an action which changes a users password, I was able to use the below:

/**
 * Implementation of hook_action_info().
 */
function userplus_actions_action_info() {
  $actions = array(
    'userplus_change_password_action' =&gt; array(
      'type' =&gt; 'user',
      'description' =&gt; t('Change user\'s password'),
      'configurable' =&gt; TRUE,
      'hooks' =&gt; array(),
    ),
  );
  return $actions;
}

/**
 * Action to change a user's password
 */
function userplus_change_password_action_form($context) {
  _user_password_dynamic_validation();
  $form['pass'] = array(
    '#title' =&gt; t('New password'),
    '#type' =&gt; 'password_confirm',
    '#description' =&gt; t('Provide a password for the selected users in both fields.'),
    '#required' =&gt; TRUE,
    '#size' =&gt; 25,
  );

  return $form;
}

function userplus_change_password_action_submit($form, $form_state) {
  return array('pass' =&gt; $form_state['values']['pass']);
}

function userplus_change_password_action(&amp;$user, $context) {
  user_save($user, array('pass' =&gt; $context['pass']));
}