diff --git a/addons/account/models/ir_attachment.py b/addons/account/models/ir_attachment.py
index 518fdc6001f..9bb3befbcc7 100644
--- a/addons/account/models/ir_attachment.py
+++ b/addons/account/models/ir_attachment.py
@@ -100,7 +100,7 @@ class IrAttachment(models.Model):
             # XML attachments received by mail have a 'text/plain' mimetype (cfr. context key:
             # 'attachments_mime_plainxml'). Therefore, if content start with '<?xml', or if the filename ends with
             # '.xml', it is considered as XML.
-            is_text_plain_xml = 'text/plain' in attachment.mimetype and (attachment.raw.startswith(b'<?xml') or attachment.name.endswith('.xml'))
+            is_text_plain_xml = 'text/plain' in attachment.mimetype and (attachment.raw and attachment.raw.startswith(b'<?xml') or attachment.name.endswith('.xml'))
             return attachment.mimetype.endswith('/xml') or is_text_plain_xml
 
         return [