https://motherboard.vice.com/en_us/article/a3q374/hacker-bios-firmware-backdoor-evil-maid-attack-laptop-5-minutes

Hacker lore is littered with tales of mysterious attackers breaking into hotels—perhaps at a conference—to get their hands on someone’s laptop with the goal of installing malware on it by physically connecting to the machine. That’s why the more careful hackers never leave their laptops unattended at events, or bring disposable computers with little to nothing valuable on them.

These types of attacks are called evil maid attacks in the infosec world, because the imaginary attacker is someone who has access to your room and malicious intentions. Pwning a laptop via physical access is a true and tested method to hack someone. But there’s no better way to be reminded of how effective and sometimes effortless these attacks can be than an actual demo.