diff --git a/internal/proxy/director/layer/authn/layer-options.json b/internal/proxy/director/layer/authn/layer-options.json
index cb08c53..e53635c 100644
--- a/internal/proxy/director/layer/authn/layer-options.json
+++ b/internal/proxy/director/layer/authn/layer-options.json
@@ -43,5 +43,6 @@
                 }
             }
         }
-    }
+    },
+    "additionalProperties": false
 }
\ No newline at end of file