diff --git a/Gemfile.lock b/Gemfile.lock
index 3613ccb..c4f7969 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -67,7 +67,7 @@ GEM
     power_assert (0.2.6)
     psych (2.2.4)
     public_suffix (2.0.5)
-    rack (2.0.1)
+    rack (2.2.6.4)
     rake (12.0.0)
     rdoc (3.12.2)
       json (~> 1.4)