There's procedure to leave a tray on corridor and have cabin crew protect it so people cant just jump in cabin. Pilot also can check camera and deny the open.

There's procedure to leave a tray on corridor and have cabin crew protect it so people cant just jump in cabin. Pilot also can check camera and deny the open. So having a successful takeover depends on multiple failures at same time... chernobyl happened so its not impossible but much less likely then before. At this point id be more worried about pilots or malware on flight computers.