Nikolaj Schlej, of UEFITool fame, has a series of articles on UEFI security; so far there are 4 parts to this series. It is written in Russian. If you can’t use translation tools effectively — like me — this series is a good time to start to learn. Here’s the excerpted output of Google Translate of the first paragraph of part 1:
In this article, we will focus on models of threats and attack vectors on UEFI, as well as protection against overwriting the contents of the chip BIOS – the most devastating of the possible consequences of an attack. If you are curious about how to protect UEFI and which vulnerabilities in it and remain uncorrected in most modern systems – welcome under the cut.
http://habrahabr.ru/users/CodeRush/topics/
part 1:
http://habrahabr.ru/post/266935/
part 2:
http://habrahabr.ru/post/267197/
part 3:
http://habrahabr.ru/post/267237/
part 4:
http://habrahabr.ru/post/267491/
Firmware Security 