Anycubic users say their 3D printers were hacked to warn of a security flaw

TechCrunch and user reports indicate Anycubic 3D printers received a planted text file warning of a "critical vulnerability" in the company's MQTT service that allegedly allows remote connection/control; the message advised disconnecting printers from the internet, the Anycubic app showed outages, and the author claimed to have messaged millions of devices though that figure is unconfirmed.