In January 2018, the entire computer industry was put on alert by two new processor vulnerabilities dubbed Meltdown and Spectre that defeated the fundamental OS security boundaries separating kernel and user space memory. The flaws stemmed from a performance feature of modern CPUs known as speculative execution and mitigating them required one of the biggest patch coordination efforts in history, involving CPU makers, device manufacturers and operating system vendors.
Meltdown and Spectre were certainly not the first vulnerabilities to result from a hardware design decision, but their widespread impact sparked the interest of the security research community into such flaws. Since then, many researchers, both from academia and the private sector, have been studying the low-level operation of CPUs and other hardware components and have been uncovering more and more issues.