diff --git a/flaschengeist/plugins/auth/__init__.py b/flaschengeist/plugins/auth/__init__.py
index ef84ae7..9889e04 100644
--- a/flaschengeist/plugins/auth/__init__.py
+++ b/flaschengeist/plugins/auth/__init__.py
@@ -36,7 +36,7 @@ def login():
     try:
         userid = data["userid"]
         password = data["password"]
-    except KeyError:
+    except (KeyError, ValueError):
         raise BadRequest("Missing parameter(s)")
 
     logger.debug("search user {{ {} }} in database".format(userid))