diff --git a/examples/sinatra/Gemfile.lock b/examples/sinatra/Gemfile.lock
index bfe540125..ddc3c08ca 100644
--- a/examples/sinatra/Gemfile.lock
+++ b/examples/sinatra/Gemfile.lock
@@ -4,7 +4,7 @@ GEM
     minitest (2.5.1)
     mustermann (1.1.1)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.3.1)
+    rack (2.2.6.3)
     rack-protection (2.2.0)
       rack
     rack-test (0.6.1)