diff --git a/src/pretix/base/models/base.py b/src/pretix/base/models/base.py
index 137b3c1af..83c7b1bc8 100644
--- a/src/pretix/base/models/base.py
+++ b/src/pretix/base/models/base.py
@@ -53,7 +53,7 @@ class LoggingMixin:
             event = self
         elif hasattr(self, 'event'):
             event = self.event
-        if not user.is_authenticated:
+        if user and not user.is_authenticated:
             user = None
         l = LogEntry(content_object=self, user=user, action_type=action, event=event, api_token=api_token)
         if data: