Merge branch 'MAGETWO-92177' into 2.1.15-bugfixes-010818

Author: Dmytro Voskoboinikov

app/code/Magento/Customer/Controller/Adminhtml/Index/AbstractMassAction.php

@@ -10,6 +10,7 @@
 use Magento\Framework\App\ResponseInterface;
 use Magento\Framework\Controller\ResultInterface;
 use Magento\Backend\App\Action\Context;
+use Magento\Framework\Exception\NotFoundException;
 use Magento\Ui\Component\MassAction\Filter;
 use Magento\Customer\Model\ResourceModel\Customer\CollectionFactory;
 
@@ -60,6 +61,10 @@ public function __construct(Context $context, Filter $filter, CollectionFactory
      */
     public function execute()
     {
+        if (!$this->getRequest()->isPost()) {
+            throw new NotFoundException(__('Page not found'));
+        }
+
         try {
             $collection = $this->filter->getCollection($this->collectionFactory->create());
             return $this->massAction($collection);