diff --git a/Gemfile.lock b/Gemfile.lock
index 86dae79..6fc44dd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -39,7 +39,7 @@ GEM
     postmark (1.2.1)
       json
       rake
-    rack (1.6.11)
+    rack (1.6.13)
     rack-protection (1.5.3)
       rack
     rake (10.4.2)