Intel’s mitigations for new Spectre V2 vulnerability affect CPU performance by up to 35%
Branch History Injection (BHI) is a new variant of the Spectre V2 vulnerability that affects several Intel and Arm processors, was announced earlier this week by the Systems and Network Security Group at Vrije Universiteit Amsterdam. Tests conducted by Phoronix showed that affected processors experienced up to a 35 percent performance drop under the new BHI mitigations.
Intel plans to release security updates for the company’s affected processors, but the patching process will take longer due to the high number of affected processors. Intel’s Haswell series of processors are the most vulnerable of the company’s chips. The Linux community has launched mitigations to fix the affected CPUs on its operating system, and the kernel has been updated shortly after the vulnerability was announced.
It is conceivable that Intel and software engineers will need additional time and effort to reduce the impact of BHI mitigation. However, for now, it can be very difficult to roll out such a patch across servers and different frameworks that do a lot of I/O upgrade work.