diff --git a/examples/rails_app/Gemfile.lock b/examples/rails_app/Gemfile.lock
index 984cd5b..875ea5e 100644
--- a/examples/rails_app/Gemfile.lock
+++ b/examples/rails_app/Gemfile.lock
@@ -109,7 +109,7 @@ GEM
     public_suffix (4.0.6)
     puma (4.3.11)
       nio4r (~> 2.0)
-    rack (2.2.3)
+    rack (2.2.3.1)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (5.2.2.1)