diff --git a/Gemfile.lock b/Gemfile.lock
index 9c478a2..d56c049 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -55,7 +55,7 @@ GEM
       ast (~> 2.4.0)
     psych (3.0.2)
     racc (1.5.2)
-    rack (2.2.3)
+    rack (2.2.6.4)
     rainbow (3.0.0)
     rake (12.3.3)
     rdoc (6.3.1)