diff --git a/Gemfile.lock b/Gemfile.lock
index 95fa8ae..888f7bd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,7 +6,7 @@ GEM
     json (2.3.0)
     mustermann (2.0.2)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.4)
+    rack (2.2.6.4)
     rack-protection (2.2.3)
       rack
     ruby2_keywords (0.0.5)