diff --git a/back/engines/commercial/multi_tenancy/app/services/multi_tenancy/templates/utils.rb b/back/engines/commercial/multi_tenancy/app/services/multi_tenancy/templates/utils.rb
index a471f789ac37..f4805c338432 100644
--- a/back/engines/commercial/multi_tenancy/app/services/multi_tenancy/templates/utils.rb
+++ b/back/engines/commercial/multi_tenancy/app/services/multi_tenancy/templates/utils.rb
@@ -270,7 +270,7 @@ def parse_yml(content)
           YAML.load(
             content,
             aliases: true,
-            permitted_classes: [Date, Project, Symbol, Time]
+            permitted_classes: [Date, Time, Symbol, *ar_classes]
           )
         end
         alias parse_yaml parse_yml
@@ -283,6 +283,13 @@ def parse_yml_file(file)
 
         private
 
+        def ar_classes
+          @ar_classes ||= begin
+            Rails.application.eager_load! # Make sure all model classes are loaded.
+            ApplicationRecord.descendants
+          end
+        end
+
         def template_locales(serialized_models)
           locales = Set.new