diff --git a/Gemfile.lock b/Gemfile.lock
index ee381a8..47515e6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -23,7 +23,7 @@ GEM
     multi_xml (0.6.0)
     mustermann (1.1.1)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.3)
+    rack (2.2.6.4)
     rack-protection (2.1.0)
       rack
     ruby2_keywords (0.0.2)