A zero-day software vulnerability in the firmware of older Apple computers could be used to slip hard-to-remove malware onto a computer. A security researcher found it was possible to tamper with an Apple computer’s UEFI (unified extensible firmware interface) The code is unlocked after a computer goes to sleep and reawakens, allowing it to be modified. Vilaca wrote it is then possible to install a rootkit, a type of malware that is hard to remove and undetectable by security products.”]