diff --git a/Gemfile.lock b/Gemfile.lock
index df2a29f..9873db3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -111,7 +111,7 @@ GEM
     pg (0.18.4)
     public_suffix (2.0.4)
     puma (3.6.0)
-    rack (2.0.1)
+    rack (2.2.3)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (5.0.0.1)