Ticket #53773: 53773.diff

src/wp-admin/includes/ajax-actions.php

@@ -3003 +3003 @@
                 $total_posts = $count_query->found_posts;
         }
 
-        $max_pages = ceil( $total_posts / (int) $attachments_query->query['posts_per_page'] );
+        $posts_per_page = (int) $attachments_query->query['posts_per_page'];
+
+        $max_pages = $posts_per_page ? ceil( $total_posts / $posts_per_page ) : 0;
 
         header( 'X-WP-Total: ' . (int) $total_posts );
         header( 'X-WP-TotalPages: ' . (int) $max_pages );