diff --git a/Gemfile.lock b/Gemfile.lock
index b8fda82..70ae383 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -94,7 +94,7 @@ GEM
       mini_portile2 (~> 2.3.0)
     pg (0.21.0)
     pg (0.21.0-x64-mingw32)
-    rack (1.6.8)
+    rack (1.6.12)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (4.2.10)