http://media.ccc.de/browse/congress/2014/31c3_-_6128_-_en_-_saal_1_-_201412291830_-_thunderstrike_efi_bootkits_for_apple_macbooks_-_trammell_hudson.html

In this presentation we demonstrate Thunderstrike, a vulnerability that allows the installation of persistent firmware modifications into the EFI boot ROM of Apple's popular MacBooks. The bootkit can be easily installed by an evil-maid via the externally accessible Thunderbolt ports and can survive reinstallation of OSX as well as hard drive replacements. Once installed, it can prevent software attempts to remove it and could spread virally across air-gaps by infecting additional Thunderbolt devices.

Trammell Hudson