diff --git a/Gemfile.lock b/Gemfile.lock
index a2b3abf..7f1186e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -5,7 +5,7 @@ GEM
     erubi (1.12.0)
     mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.6.2)
+    rack (2.2.6.4)
     rack-protection (3.0.5)
       rack
     redis (5.0.6)