diff --git a/Gemfile.lock b/Gemfile.lock
index 6b18c0e..44e87fd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -4,7 +4,7 @@ GEM
     json (2.3.1)
     mustermann (1.1.1)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.3)
+    rack (2.2.6.4)
     rack-protection (2.0.8.1)
       rack
     ruby2_keywords (0.0.2)