diff --git a/Gemfile.lock b/Gemfile.lock
index 95ffb4d..a619270 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -57,7 +57,7 @@ GEM
     mysql2 (0.3.13)
     newrelic_rpm (3.6.9.171)
     polyglot (0.3.3)
-    rack (1.5.2)
+    rack (1.5.5)
     rack-test (0.6.2)
       rack (>= 1.0)
     rails (4.0.0)