diff --git a/Gemfile.lock b/Gemfile.lock
index 5c11915..a34670f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -65,7 +65,7 @@ GEM
     multipart-post (1.2.0)
     pg (0.17.1)
     polyglot (0.3.4)
-    rack (1.5.2)
+    rack (1.5.5)
     rack-test (0.6.2)
       rack (>= 1.0)
     rails (4.0.3)