diff --git a/Gemfile.lock b/Gemfile.lock
index 36cb684..46cc738 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -65,7 +65,7 @@ GEM
       byebug (~> 10.0)
       pry (~> 0.10)
     public_suffix (3.0.2)
-    rack (2.0.6)
+    rack (2.2.3)
     rainbow (3.0.0)
     rake (10.5.0)
     rspec (3.7.0)