diff --git a/telethon/tl/custom/message.py b/telethon/tl/custom/message.py
index 01397bc1..75a99632 100644
--- a/telethon/tl/custom/message.py
+++ b/telethon/tl/custom/message.py
@@ -37,6 +37,9 @@ class Message:
         self._sender = entities.get(self.original_message.from_id)
         if self._sender:
             self._input_sender = get_input_peer(self._sender)
+            if (isinstance(self._input_sender, types.InputPeerUser)
+                    and not self._input_sender.access_hash):
+                self._input_sender = None
         else:
             self._input_sender = None
 
@@ -52,6 +55,9 @@ class Message:
         self._input_chat = input_chat
         if not self._input_chat and self._chat:
             self._input_chat = get_input_peer(self._chat)
+            if not self._input_chat.access_hash:
+                # Telegram may omit the hash in updates -> invalid peer
+                self._input_chat = None
 
         if getattr(self.original_message, 'fwd_from', None):
             self._forward = Forward(