diff --git a/cloudevents/pydantic/v2/event.py b/cloudevents/pydantic/v2/event.py
index 890c03d1..4ae8bb5c 100644
--- a/cloudevents/pydantic/v2/event.py
+++ b/cloudevents/pydantic/v2/event.py
@@ -209,7 +209,7 @@ def _ce_json_dumps(self) -> typing.Dict[str, typing.Any]:
     def _get_attributes(self) -> typing.Dict[str, typing.Any]:
         return {
             key: conversion.best_effort_encode_attribute_value(value)
-            for key, value in self.__dict__.items()
+            for key, value in dict(BaseModel.__iter__(self)).items()
             if key not in ["data"]
         }