diff --git a/Gemfile.lock b/Gemfile.lock
index 729dd93..debc438 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -62,7 +62,7 @@ GEM
     nio4r (2.0.0)
     nokogiri (1.7.2)
       mini_portile2 (~> 2.1.0)
-    rack (2.0.3)
+    rack (2.0.8)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (5.1.1)