diff --git a/actionpack/lib/action_controller/metal/http_authentication.rb b/actionpack/lib/action_controller/metal/http_authentication.rb
index 032275ac64199728e88ebee9bd6c989669f9d9be..bbb38cf8fc1760ca76346ea9535a7222170dd43a 100644
--- a/actionpack/lib/action_controller/metal/http_authentication.rb
+++ b/actionpack/lib/action_controller/metal/http_authentication.rb
@@ -94,7 +94,7 @@ def authenticate(request, &login_procedure)
       end
 
       def has_basic_credentials?(request)
-        request.authorization.present? && (auth_scheme(request) == 'Basic')
+        request.authorization.present? && (auth_scheme(request).downcase == 'basic')
       end
 
       def user_name_and_password(request)
diff --git a/actionpack/test/controller/http_basic_authentication_test.rb b/actionpack/test/controller/http_basic_authentication_test.rb
index ed3632007d7b7c008a42a31e02181394abfe09ce..0a5e5402b9aaacffcdd88aa5220d8c8dec21123e 100644
--- a/actionpack/test/controller/http_basic_authentication_test.rb
+++ b/actionpack/test/controller/http_basic_authentication_test.rb
@@ -100,6 +100,14 @@ def test_encode_credentials_has_no_newline
     assert_no_match(/\n/, result)
   end
 
+  test "succesful authentication with uppercase authorization scheme" do
+    @request.env['HTTP_AUTHORIZATION'] = "BASIC #{::Base64.encode64("lifo:world")}"
+    get :index
+
+    assert_response :success
+    assert_equal 'Hello Secret', @response.body, 'Authentication failed when authorization scheme BASIC'
+  end
+
   test "authentication request without credential" do
     get :display