diff --git a/app/code/Magento/Catalog/Model/Api/SearchCriteria/CollectionProcessor/ConditionProcessor/ProductCategoryCondition.php b/app/code/Magento/Catalog/Model/Api/SearchCriteria/CollectionProcessor/ConditionProcessor/ProductCategoryCondition.php
index f70bab73d0830..d37f97c38a4f6 100644
--- a/app/code/Magento/Catalog/Model/Api/SearchCriteria/CollectionProcessor/ConditionProcessor/ProductCategoryCondition.php
+++ b/app/code/Magento/Catalog/Model/Api/SearchCriteria/CollectionProcessor/ConditionProcessor/ProductCategoryCondition.php
@@ -104,7 +104,7 @@ private function getCategoryIds(Filter $filter): array
             }
         }
 
-        return array_unique(array_merge($categoryIds, ...$childCategoryIds));
+        return array_map('intval', array_unique(array_merge($categoryIds, ...$childCategoryIds)));
     }
 
     /**
diff --git a/app/code/Magento/Catalog/Model/ProductCategoryList.php b/app/code/Magento/Catalog/Model/ProductCategoryList.php
index 5bbae772d5c2b..c8b075ffb494e 100644
--- a/app/code/Magento/Catalog/Model/ProductCategoryList.php
+++ b/app/code/Magento/Catalog/Model/ProductCategoryList.php
@@ -80,7 +80,11 @@ public function getCategoryIds($productId)
                 Select::SQL_UNION_ALL
             );
 
-            $this->categoryIdList[$productId] = $this->productResource->getConnection()->fetchCol($unionSelect);
+            $this->categoryIdList[$productId] = array_map(
+                'intval',
+                $this->productResource->getConnection()->fetchCol($unionSelect)
+            );
+
         }
 
         return $this->categoryIdList[$productId];
diff --git a/app/code/Magento/Catalog/Model/ResourceModel/Product/Collection.php b/app/code/Magento/Catalog/Model/ResourceModel/Product/Collection.php
index 0d62d120f80e0..5afac59b25db6 100644
--- a/app/code/Magento/Catalog/Model/ResourceModel/Product/Collection.php
+++ b/app/code/Magento/Catalog/Model/ResourceModel/Product/Collection.php
@@ -1809,7 +1809,8 @@ protected function _productLimitationJoinWebsite()
             }
             $conditions[] = $this->getConnection()->quoteInto(
                 'product_website.website_id IN(?)',
-                $filters['website_ids']
+                $filters['website_ids'],
+                'int'
             );
         } elseif (isset(
             $filters['store_id']
@@ -1821,7 +1822,7 @@ protected function _productLimitationJoinWebsite()
         ) {
             $joinWebsite = true;
             $websiteId = $this->_storeManager->getStore($filters['store_id'])->getWebsiteId();
-            $conditions[] = $this->getConnection()->quoteInto('product_website.website_id = ?', $websiteId);
+            $conditions[] = $this->getConnection()->quoteInto('product_website.website_id = ?', $websiteId, 'int');
         }
 
         $fromPart = $this->getSelect()->getPart(\Magento\Framework\DB\Select::FROM);
@@ -2017,12 +2018,16 @@ protected function _applyProductLimitations()
 
         $conditions = [
             'cat_index.product_id=e.entity_id',
-            $this->getConnection()->quoteInto('cat_index.store_id=?', $filters['store_id']),
+            $this->getConnection()->quoteInto('cat_index.store_id=?', $filters['store_id'], 'int'),
         ];
         if (isset($filters['visibility']) && !isset($filters['store_table'])) {
-            $conditions[] = $this->getConnection()->quoteInto('cat_index.visibility IN(?)', $filters['visibility']);
+            $conditions[] = $this->getConnection()->quoteInto(
+                'cat_index.visibility IN(?)',
+                $filters['visibility'],
+                'int'
+            );
         }
-        $conditions[] = $this->getConnection()->quoteInto('cat_index.category_id=?', $filters['category_id']);
+        $conditions[] = $this->getConnection()->quoteInto('cat_index.category_id=?', $filters['category_id'], 'int');
         if (isset($filters['category_is_anchor'])) {
             $conditions[] = $this->getConnection()->quoteInto('cat_index.is_parent=?', $filters['category_is_anchor']);
         }
diff --git a/lib/internal/Magento/Framework/Mview/View.php b/lib/internal/Magento/Framework/Mview/View.php
index a937c62dfc23a..589034886010f 100644
--- a/lib/internal/Magento/Framework/Mview/View.php
+++ b/lib/internal/Magento/Framework/Mview/View.php
@@ -283,7 +283,7 @@ public function update()
                 for ($vsFrom = $lastVersionId; $vsFrom < $currentVersionId; $vsFrom += $versionBatchSize) {
                     // Don't go past the current version for atomicy.
                     $versionTo = min($currentVersionId, $vsFrom + $versionBatchSize);
-                    $ids = $this->getChangelog()->getList($vsFrom, $versionTo);
+                    $ids = array_map('intval', $this->getChangelog()->getList($vsFrom, $versionTo));
 
                     // We run the actual indexer in batches.
                     // Chunked AFTER loading to avoid duplicates in separate chunks.