Brossard, who is CEO and security research engineer at French security company Toucan System, demonstrated how the malware works at the Defcon hacker conference on Saturday, after also presenting it at the Black Hat security conference on Thursday.

Rakshasa, named after a demon from the Hindu mythology, is not the first malware to target the BIOS -- the low-level motherboard firmware that initializes other hardware components. However, it differentiates itself from similar threats by using new tricks to achieve persistency and evade detection.

Rakshasa replaces the motherboard BIOS, but can also infect the PCI firmware of other peripheral devices like network cards or CD-ROMs, in order to achieve a high degree of redundancy.

Rakshasa was built with open source software. It replaces the vendor-supplied BIOS with a combination of Coreboot and SeaBIOS, alternatives that work on a variety of motherboards from different manufacturers, and also writes an open source network boot firmware called iPXE to the computer's network card.

All of these components have been modified so they don't display anything that could give their presence away during the booting process. Coreboot even supports custom splashscreens that can mimic the ones of the replaced BIOSes.