diff --git a/Gemfile.lock b/Gemfile.lock
index 9f97776..e7154dd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -42,7 +42,7 @@ GEM
       method_source (~> 0.8.1)
       slop (~> 3.4)
     public_suffix (2.0.5)
-    rack (2.0.6)
+    rack (2.1.4)
     rack-protection (2.0.2)
       rack
     rake (11.2.2)