diff --git a/Gemfile.lock b/Gemfile.lock
index 406012b..30b78ea 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -33,7 +33,7 @@ GEM
     mustermann (1.0.3)
     pg (1.1.4)
     public_suffix (4.0.1)
-    rack (2.0.7)
+    rack (2.1.4)
     rack-contrib (2.1.0)
       rack (~> 2.0)
     rack-parser (0.7.0)