diff --git a/Gemfile.lock b/Gemfile.lock
index 7bc9917b9..e159c2e7d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -85,7 +85,7 @@ GEM
     polyglot (0.3.3)
     puma (1.6.3)
       rack (~> 1.2)
-    rack (1.4.1)
+    rack (1.4.2)
     rack-cache (1.2)
       rack (>= 0.4)
     rack-pjax (0.6.0)