diff --git a/app/builders/messages/message_builder.rb b/app/builders/messages/message_builder.rb
index e9bf0802b..69ed786ce 100644
--- a/app/builders/messages/message_builder.rb
+++ b/app/builders/messages/message_builder.rb
@@ -35,7 +35,13 @@ class Messages::MessageBuilder
         file: uploaded_attachment
       )
 
-      attachment.file_type = file_type(uploaded_attachment&.content_type) if uploaded_attachment.is_a?(ActionDispatch::Http::UploadedFile)
+      attachment.file_type = if uploaded_attachment.is_a?(String)
+                               file_type_by_signed_id(
+                                 uploaded_attachment
+                               )
+                             else
+                               file_type(uploaded_attachment&.content_type)
+                             end
     end
   end
 
diff --git a/app/helpers/file_type_helper.rb b/app/helpers/file_type_helper.rb
index db3f6249d..03b807aad 100644
--- a/app/helpers/file_type_helper.rb
+++ b/app/helpers/file_type_helper.rb
@@ -8,6 +8,12 @@ module FileTypeHelper
     :file
   end
 
+  # Used in case of DIRECT_UPLOADS_ENABLED=true
+  def file_type_by_signed_id(signed_id)
+    blob = ActiveStorage::Blob.find_signed(signed_id)
+    file_type(blob&.content_type)
+  end
+
   def image_file?(content_type)
     [
       'image/jpeg',
diff --git a/spec/builders/messages/message_builder_spec.rb b/spec/builders/messages/message_builder_spec.rb
index 6227f2a48..b17f752db 100644
--- a/spec/builders/messages/message_builder_spec.rb
+++ b/spec/builders/messages/message_builder_spec.rb
@@ -50,5 +50,33 @@ describe ::Messages::MessageBuilder do
         expect(message.message_type).to eq params[:message_type]
       end
     end
+
+    context 'when attachment messages' do
+      let(:params) do
+        ActionController::Parameters.new({
+                                           content: 'test',
+                                           attachments: [Rack::Test::UploadedFile.new('spec/assets/avatar.png', 'image/png')]
+                                         })
+      end
+
+      it 'creates message with attachments' do
+        message = message_builder
+        expect(message.attachments.first.file_type).to eq 'image'
+      end
+
+      context 'when DIRECT_UPLOAD_ENABLED' do
+        let(:params) do
+          ActionController::Parameters.new({
+                                             content: 'test',
+                                             attachments: [get_blob_for('spec/assets/avatar.png', 'image/png').signed_id]
+                                           })
+        end
+
+        it 'creates message with attachments' do
+          message = message_builder
+          expect(message.attachments.first.file_type).to eq 'image'
+        end
+      end
+    end
   end
 end
diff --git a/spec/rails_helper.rb b/spec/rails_helper.rb
index 517f336a0..3b42c77ff 100644
--- a/spec/rails_helper.rb
+++ b/spec/rails_helper.rb
@@ -64,6 +64,7 @@ RSpec.configure do |config|
   # arbitrary gems may also be filtered via:
   # config.filter_gems_from_backtrace("gem name")
   config.include SlackStubs
+  config.include FileUploadHelpers
   config.include Devise::Test::IntegrationHelpers, type: :request
   config.include ActiveSupport::Testing::TimeHelpers
   config.include ActionCable::TestHelper
diff --git a/spec/support/file_upload_helpers.rb b/spec/support/file_upload_helpers.rb
new file mode 100644
index 000000000..fa4e577cf
--- /dev/null
+++ b/spec/support/file_upload_helpers.rb
@@ -0,0 +1,9 @@
+module FileUploadHelpers
+  def get_blob_for(file_path, content_type)
+    ActiveStorage::Blob.create_and_upload!(
+      io: File.open(file_path, 'rb'),
+      filename: File.basename(file_path),
+      content_type: content_type
+    )
+  end
+end