The expert devised two attacks dubbed Meltdown (CVE-2017-5754) and Spectre (CVE-2017-5753 and CVE-2017-5715), which could be conducted to sensitive data processed by the CPU.
Both attacks leverage the “speculative execution” technique used by most modern CPUs to optimize performance.
To protect systems from bot Meltdown and Spectre attacks it is possible to implement the hardening technique known as kernel page table isolation (KPTI). The technique allows isolating kernel space from user space memory.
Intel confirmed that system manufacturers have been provided firmware and software updates that neutralize both Meltdown and Spectre attacks for chips launched in the last five years.
Customers have to wait that system manufacturers will distribute the security patches for their affected products.
According to Intel, by the end of the next week, the company will have issued security patches for more than 90% of chips commercialized in the past 5 years.
“Intel has developed and is rapidly issuing updates for all types of Intel-based computer systems — including personal computers and servers — that render those systems immune from both exploits (referred to as “Spectre” and “Meltdown”) reported by Google Project Zero.” reads the press release published by Intel.
“Intel has already issued updates for the majority of processor products introduced within the past five years. By the end of next week, Intel expects to have issued updates for more than 90 percent of processor products introduced within the past five years.”
Experts speculate security patches could have a significant effect on the performance of the affected products, but Intel pointed out that average users will not notice any difference.
“Intel continues to believe that the performance impact of these updates is highly workload-dependent and, for the average computer user, should not be significant and will be mitigated over time.” continues Intel.
“While on some discrete workloads the performance impact from the software updates may initially be higher, additional post-deployment identification, testing and improvement of the software updates should mitigate that impact.”
Intel confirmed that extensive testing conducted by tech giants (Apple, Amazon, Google, and Microsoft) to assess any impact on system performance from security updates did not reveal negative effects.
Researchers from Google Project Zero proposed as mitigation strategy a technique named Retpoline.
“In response to the vulnerabilities that were discovered we developed a novel mitigation called “Retpoline” — a binary modification technique that protects against “branch target injection” attacks. We shared Retpoline with our industry partners and have deployed it on Google’s systems, where we have observed negligible impact on performance.” wrote Google.
“In addition, we have deployed Kernel Page Table Isolation (KPTI) — a general purpose technique for better protecting sensitive information in memory from other software running on a machine — to the entire fleet of Google Linux production servers that support all of our products, including Search, Gmail, YouTube, and Google Cloud Platform.”
My Italian readers can watch the video I made on this specific topic:
(Security Affairs – Meltdown and Spectre attacks, CPU)