Backdoor in the Core - Altering Intel x86 Instruction Set at Runtime

Explore groundbreaking research on Intel CPU microcode security vulnerabilities in this DEF CON 31 conference presentation that reveals how to persistently alter x86 instruction sets at runtime. Learn about the reverse-engineering of complex x86 instructions on Intel Goldmont CPUs, leading to the discovery of hidden microcode mechanisms and their circumvention. Discover newly developed microcode tracing tools that enable deeper dynamic analysis of Intel Atom microcode, accompanied by a practical C library for implementing microcode modifications. Understand the significant security implications of unverifiable vendor microcode updates through a demonstration of how attackers can compromise Linux systems by implementing backdoors within CPU core microcode.