diff --git a/Gemfile.lock b/Gemfile.lock
index fc71435..0479071 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -8,7 +8,7 @@ GEM
       git (>= 1.2.5)
       rake
     kgio (2.6.0)
-    rack (1.3.2)
+    rack (2.2.3)
     raindrops (0.7.0)
     rake (0.9.2)
     rcov (0.9.10)