diff --git a/vendor/magento/module-elasticsearch/SearchAdapter/Query/Builder/Sort.php b/vendor/magento/module-elasticsearch/SearchAdapter/Query/Builder/Sort.php
index 296a71eda5c6..869a350aae7d 100644
--- a/vendor/magento/module-elasticsearch/SearchAdapter/Query/Builder/Sort.php
+++ b/vendor/magento/module-elasticsearch/SearchAdapter/Query/Builder/Sort.php
@@ -89,8 +89,7 @@ public function getSort(RequestInterface $request)
             if (in_array($item['field'], $this->skippedFields)) {
                 continue;
             }
-            $itemField = $item['field'] != null ? $item['field'] : '';
-            $attribute = $this->attributeAdapterProvider->getByAttributeCode($itemField);
+            $attribute = $this->attributeAdapterProvider->getByAttributeCode((string)$item['field']);
             $fieldName = $this->fieldNameResolver->getFieldName($attribute);
             if (isset($this->map[$fieldName])) {
                 $fieldName = $this->map[$fieldName];
diff --git a/vendor/magento/module-product-alert/Model/Mailing/AlertProcessor.php b/vendor/magento/module-product-alert/Model/Mailing/AlertProcessor.php
index 83ac4abd896c..12abfa64b427 100644
--- a/vendor/magento/module-product-alert/Model/Mailing/AlertProcessor.php
+++ b/vendor/magento/module-product-alert/Model/Mailing/AlertProcessor.php
@@ -139,6 +139,7 @@ public function process(string $alertType, array $customerIds, int $websiteId):
      * @param int $websiteId
      * @return array
      * @throws \Exception
+     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
      */
     private function processAlerts(string $alertType, array $customerIds, int $websiteId): array
     {
@@ -160,6 +161,7 @@ private function processAlerts(string $alertType, array $customerIds, int $websi
         /** @var Website $website */
         $website = $this->storeManager->getWebsite($websiteId);
         $defaultStoreId = $website->getDefaultStore()->getId();
+        $products = [];
 
         /** @var Price|Stock $alert */
         foreach ($collection as $alert) {
@@ -174,7 +176,12 @@ private function processAlerts(string $alertType, array $customerIds, int $websi
                     $customer = $this->customerRepository->getById($alert->getCustomerId());
                 }
 
-                $product = $this->productRepository->getById($alert->getProductId(), false, $defaultStoreId);
+                if (!isset($products[$alert->getProductId()])) {
+                    $product = $this->productRepository->getById($alert->getProductId(), false, $defaultStoreId, true);
+                    $products[$alert->getProductId()] = $product;
+                } else {
+                    $product = $products[$alert->getProductId()];
+                }
 
                 switch ($alertType) {
                     case self::ALERT_TYPE_STOCK:
diff --git a/vendor/magento/framework/Filter/Input/MaliciousCode.php b/vendor/magento/framework/Filter/Input/MaliciousCode.php
index 7048d85be3c7..a6fa7d69c622 100644
--- a/vendor/magento/framework/Filter/Input/MaliciousCode.php
+++ b/vendor/magento/framework/Filter/Input/MaliciousCode.php
@@ -47,7 +47,7 @@ public function filter($value)
     {
         $replaced = 0;
         do {
-            $value = preg_replace($this->_expressions, '', $value, -1, $replaced);
+            $value = preg_replace($this->_expressions, '', $value ?? '', -1, $replaced);
         } while ($replaced !== 0);
         return  $value;
     }