diff --git a/Gemfile.lock b/Gemfile.lock
index 899a3a9..3875415 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -12,7 +12,7 @@ GEM
     mustermann (1.0.3)
     net-http-persistent (3.0.1)
       connection_pool (~> 2.2)
-    rack (2.2.3)
+    rack (2.2.3.1)
     rack-protection (2.0.5)
       rack
     sinatra (2.0.5)