diff --git a/Gemfile b/Gemfile
index a32b7ffbf..a73c32d0b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,7 +3,7 @@ source 'https://rubygems.org'
 ruby '>= 2.6.0', '< 3.2.0'
 gem 'bundler', '>= 1.12.0'
 
-gem 'rails', '6.1.6'
+gem 'rails', '6.1.6.1'
 gem 'rouge', '~> 3.29.0'
 gem 'request_store', '~> 1.5.0'
 gem 'mini_mime', '~> 1.1.0'
diff --git a/config/application.rb b/config/application.rb
index bba468f38..0a2d2f1fc 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -32,6 +32,10 @@ module RedmineApp
 
     config.active_record.store_full_sti_class = true
     config.active_record.default_timezone = :local
+    config.active_record.yaml_column_permitted_classes = [
+      Symbol,
+      ActiveSupport::HashWithIndifferentAccess
+    ]
 
     config.action_mailer.delivery_job = "ActionMailer::MailDeliveryJob"