Fix "vevent" KeyError in caldav component (#61718)

homeassistant/components/caldav/calendar.py

@@ -161,6 +161,9 @@ class WebDavCalendarData:
         )
         event_list = []
         for event in vevent_list:
+            if not hasattr(event.instance, "vevent"):
+                _LOGGER.warning("Skipped event with missing 'vevent' property")
+                continue
             vevent = event.instance.vevent
             if not self.is_matching(vevent, self.search):
                 continue
@@ -198,6 +201,9 @@ class WebDavCalendarData:
         # and they would not be properly parsed using their original start/end dates.
         new_events = []
         for event in results:
+            if not hasattr(event.instance, "vevent"):
+                _LOGGER.warning("Skipped event with missing 'vevent' property")
+                continue
             vevent = event.instance.vevent
             for start_dt in vevent.getrruleset() or []:
                 _start_of_today = start_of_today