diff --git a/core/lib/Drupal/Core/Entity/EntityAccessCheck.php b/core/lib/Drupal/Core/Entity/EntityAccessCheck.php
index d15b7f5..99bba7c 100644
--- a/core/lib/Drupal/Core/Entity/EntityAccessCheck.php
+++ b/core/lib/Drupal/Core/Entity/EntityAccessCheck.php
@@ -48,7 +48,8 @@ public function access(Route $route, RouteMatchInterface $route_match, AccountIn
     $parameters = $route_match->getParameters();
     // If there is valid entity of the given entity type, check its access.
     foreach ($route->getOption('parameters') as $name => $options) {
-      if (isset($options['type']) && $options['type'] == 'entity:' . $entity_type && ($entity = $parameters->get($name)) && $entity instanceof EntityInterface) {
+      $option_entity_type = $this->getEntityTypeFromDefaults($options, $route_match->getRawParameters()->all());
+      if (isset($options['type']) && $option_entity_type == $entity_type && ($entity = $parameters->get($name)) && $entity instanceof EntityInterface) {
         return $entity->access($operation, $account, TRUE);
       }
     }
@@ -58,4 +59,26 @@ public function access(Route $route, RouteMatchInterface $route_match, AccountIn
     return AccessResult::neutral();
   }
 
+  /**
+   * Determines the entity type ID given a route definition and route defaults.
+   *
+   * @param mixed $definition
+   *   The parameter definition provided in the route options.
+   * @param array $defaults
+   *   The route defaults array.
+   *
+   * @return string
+   *   The entity type ID.
+   */
+  protected function getEntityTypeFromDefaults($definition, array $defaults) {
+    $entity_type_id = substr($definition['type'], strlen('entity:'));
+
+    // If the entity type is dynamic, it will be pulled from the route defaults.
+    if (strpos($entity_type_id, '{') === 0) {
+      $entity_type_slug = substr($entity_type_id, 1, -1);
+      $entity_type_id = $defaults[$entity_type_slug];
+    }
+    return $entity_type_id;
+  }
+
 }