--- /dev/null
+<?php
+
+namespace Drupal\system\Access;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Routing\Access\AccessInterface;
+
+/**
+ * Access check for cron routes.
+ */
+class CronAccessCheck implements AccessInterface {
+
+ /**
+ * Checks access.
+ *
+ * @param string $key
+ * The cron key.
+ *
+ * @return \Drupal\Core\Access\AccessResultInterface
+ * The access result.
+ */
+ public function access($key) {
+ if ($key != \Drupal::state()->get('system.cron_key')) {
+ \Drupal::logger('cron')->notice('Cron could not run because an invalid key was used.');
+ return AccessResult::forbidden()->setCacheMaxAge(0);
+ }
+ elseif (\Drupal::state()->get('system.maintenance_mode')) {
+ \Drupal::logger('cron')->notice('Cron could not run because the site is in maintenance mode.');
+ return AccessResult::forbidden()->setCacheMaxAge(0);
+ }
+ return AccessResult::allowed()->setCacheMaxAge(0);
+ }
+
+}