diff --git a/Gemfile.lock b/Gemfile.lock
index d2ed9981603..4fc36bf86cc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -41,7 +41,7 @@ PATH
       actionview (= 5.0.0.alpha)
       activesupport (= 5.0.0.alpha)
       rack (~> 1.6)
-      rack-test (~> 0.6.2)
+      rack-test (~> 0.6.3)
       rails-dom-testing (~> 1.0, >= 1.0.5)
       rails-html-sanitizer (~> 1.0, >= 1.0.1)
     actionview (5.0.0.alpha)
diff --git a/actionpack/actionpack.gemspec b/actionpack/actionpack.gemspec
index d9b23ad4a99..d907001bd69 100644
--- a/actionpack/actionpack.gemspec
+++ b/actionpack/actionpack.gemspec
@@ -22,7 +22,7 @@ Gem::Specification.new do |s|
   s.add_dependency 'activesupport', version
 
   s.add_dependency 'rack',      '~> 1.6'
-  s.add_dependency 'rack-test', '~> 0.6.2'
+  s.add_dependency 'rack-test', '~> 0.6.3'
   s.add_dependency 'rails-html-sanitizer', '~> 1.0', '>= 1.0.1'
   s.add_dependency 'rails-dom-testing', '~> 1.0', '>= 1.0.5'
   s.add_dependency 'actionview', version