diff --git a/Gemfile b/Gemfile
index 78b924b..54c5a9d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,7 @@ group :test do
   gem 'faraday-retry', '~> 2.0'
   gem 'webrick', '~> 1.9.1'
   if ENV['RACK_VERSION'] == '2'
-    gem 'rack', '>= 2.0', '< 3.0'
+    gem 'rack', '>= 2.0', '< 3.2.5'
   else
     gem 'rack', '>= 3.0', '< 4.0'
     gem 'rackup', '~> 2.0'