CSides Canberra

Grub Bootloader bugs and framework

Collecting Grub is the bootloader most commonly used in Linux desktops and servers. A bug in grub can be used for either bypassing secure boot, or maintaining persistence across a reboot once root has been achieved. This talk looks at a variety of bugs found in grub. I'll also discuss a framework for disabling secure boot utilising the grub configuration language. This is made more difficult that typical programming idioms aren't supported in the configuration language. For example, arithmetic is not native to the language, which makes mining memory difficult and hinders programming constructs such as iteration. However, arithmetic can be achieved through the use of the configuration langauge when it implements regular expressions and text substitution.

Dr Silvio Cesare

Dr Silvio Cesare is a founder and Director at InfoSect, a vulnerability research company. He has worked in technical roles and been involved in computer security for over 29 years. This period includes time in Silicon Valley in the USA, France, and Australia. He has worked commercially in both defensive and offensive roles within engineering. He was previously the Director for Education and Training at UNSW Canberra Cyber, ensuring quality content and delivery. In his early career, he was the lead architect and developer for the startup Qualys, now the industry standard in vulnerability management. He has a Ph.D. from Deakin University and has published in academia, having been cited over 1000 times on google scholar. He is a 4-time speaker and also a trainer at the international industry leading Black Hat conference. He has taken his University research through commercialisation and authored a book (Software Similarity and Classification, published by Springer).