Rambus security experts weigh in on Meltdown and Spectre

The Meltdown and Spectre cybersecurity flaws have been in the news lately, prompted by a Google Project Zero blog post in which Jann Horn writes, “We have discovered that CPU data cache timing can be abused to efficiently leak information out of mis-speculated execution, leading to (at worst) arbitrary virtual memory read vulnerabilities across local security boundaries in various contexts.” The Wall Street Journal offers a simplified description of “speculative execution,” complete with a graphic with a trashcan icon, demonstrating how hackers could sort through a CPU’s virtual rubbish to reconstruct sensitive data.

A spokesperson for Rambus notes that two Rambus employees were part of the teams that discovered the flaws: Paul Kocher, senior technical adviser, and Mike Hamburg, senior security engineer. “From Rambus’s perspective, securing processors should start at the core,” the spokesperson wrote in an email message. “Embracing a hardware-first strategy and implementing the necessary functionality on the SoC level is a key element of fully securing devices and platforms.”

Rambus in a blog post provides its point of view on how to mitigate these issues. “Despite affecting system performance in certain cases, Meltdown is a vulnerability that should be patched immediately,” Hamburg says. “However, beyond short-term solutions such as patching, the semiconductor industry should seriously consider designing chips that run sensitive cryptographic functions in a physically separate secure core, siloed away from the CPU. This design approach will go a long way in helping to prevent vulnerabilities that can be exploited by Meltdown and Spectre.”

The blog post notes that Kocher sees the Spectre threat as negatively affecting the industry for decades. “Whereas Meltdown is an urgent crisis, Spectre affects virtually all fast microprocessors. We’ve really screwed up,” Kocher told The New York Times. “There’s been this desire from the industry to be as fast as possible and secure at the same time. Spectre shows that you cannot have both.” Kocher suggests a fix may require a new generation of chips.

The Rambus blog post notes that the U.S. Department of Homeland Security (DHS) recently recommended the use of computer chips that integrate security at the transistor level to provide encryption and anonymity.

“As Meltdown and Spectre illustrate, the importance of adopting a hardware-based approach at the most basic core level cannot be overemphasized,” the post concludes. “Aside from ensuring fundamental chip security during manufacturing, embedding a separate security IP core into a SoC can help manufacturers design devices, platforms, and systems that remain secure throughout their respective lifecycles.”