diff --git a/lib/utils/config_validator/index.ts b/lib/utils/config_validator/index.ts
index a05c6d266..49c927f49 100644
--- a/lib/utils/config_validator/index.ts
+++ b/lib/utils/config_validator/index.ts
@@ -51,6 +51,8 @@ export const validateDatafile = function(datafile: unknown): any {
     if (SUPPORTED_VERSIONS.indexOf(datafile['version' as keyof unknown]) === -1) {
       throw new OptimizelyError(INVALID_DATAFILE_VERSION, datafile['version' as keyof unknown]);
     }
+  } else {
+    throw new OptimizelyError(INVALID_DATAFILE_MALFORMED);
   }
 
   return datafile;