By infecting the firmware that runs immediately before the operating system loads, these UEFI bootkits continue to run even when the hard drive is replaced or reformatted. Now the same type of chip-dwelling malware has been found in the wild for backdooring Linux machines.

Dubbed Bootkitty by its creators who go by the name BlackCat, the bootkit is assessed to be a proof-of-concept (PoC) and there is no evidence that it has been put to use in real-world attacks. Also tracked as IranuKit, it was uploaded to the VirusTotal platform on November 5, 2024.

This appears to be the first UEFI bootkit that goes beyond Windows and targets Linux machines, according to ESET security researchers.

Bootkitty doesn’t bite… yet Security researchers say they've stumbled upon the first-ever UEFI bootkit targeting Linux, illustrating a key moment in the evolution of such tools.… Dubbed "Bootkitty" by Slovak security shop ESET,

ESET's discovery of the first UEFI bootkit designed for Linux sendss an important message: UEFI bootkits are no longer confined to Windows systems alone.