diff --git a/src/SimpleSAML/Module.php b/src/SimpleSAML/Module.php
index cb3d9be3bf55ca3d65254f17ba0630df9bb13e5a..6268dc41bed40451f80916e5e2b7bd7456213bcf 100644
--- a/src/SimpleSAML/Module.php
+++ b/src/SimpleSAML/Module.php
@@ -328,8 +328,8 @@ class Module
         }
 
 
-        $assetConfig = $config->getConfigItem('assets');
-        $cacheConfig = $assetConfig->getConfigItem('caching');
+        $assetConfig = $config->getOptionalConfigItem('assets', []);
+        $cacheConfig = $assetConfig->getOptionalConfigItem('caching', []);
         $response = new BinaryFileResponse($path);
         $response->setCache([
             // "public" allows response caching even if the request was authenticated,