diff --git a/Gemfile.lock b/Gemfile.lock
index 9c5a0cd..4bc1cd3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -105,7 +105,7 @@ GEM
       rack (>= 1.2, < 3)
     psych (2.2.1)
     public_suffix (5.0.0)
-    rack (2.0.7)
+    rack (2.2.4)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (5.0.0.1)