CSRF Attack on Logout Menu

By Default, Drupal 6 Menus are Vulnerable to CSRF Attack. To Overcome this, try with Tokens module. 

Create a custom module and append the token with the URL. A sample module to avoid CSRF on Logout menu is illustrated below:

<?php
menu_cache_clear($menu_name = 'navigation');

function csrfval_menu_alter(&$items) {
    $items['logout']['page callback'] = 'csrfval_logout';
    $items['logout']['type'] = MENU_CALLBACK; 
    return $items;
}

function csrfval_logout($token = NULL) {
  if (drupal_valid_token($token)) {
      user_logout();
  }
  else {
     drupal_goto();
  }
}