diff --git a/Gemfile.lock b/Gemfile.lock
index 2c80f70..0494580 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -55,7 +55,7 @@ GEM
     minitest (4.7.5)
     multi_json (1.9.2)
     polyglot (0.3.4)
-    rack (1.5.2)
+    rack (1.5.5)
     rack-test (0.6.2)
       rack (>= 1.0)
     rails (4.0.3)