Security News > 2022 > March > Another data-leaking Spectre bug found, smashes Intel, Arm defenses

Intel this month published an advisory to address a novel Spectre v2 vulnerability in its processors that can be exploited by malware to steal data from memory that should otherwise be off limits.

Spectre is one of two closely related chip architecture blunders, details of which emerged in 2018; the other being Meltdown that The Register first highlighted.

The VU team said AMD is not affected by BHI. As we've noted before with the Spectre and Meltdown family, if malware really wanted to steal information from, say, the kernel it would probably use a privilege-escalation hole in the operating system to achieve this, rather than gradually extract data via the processor's inner mechanisms.

The VU BHI research, according to Intel researchers, prompted Intel's partners to ask whether AMD's LFENCE/JMP software mitigation for Spectre v2 on x86 processors - passed over in favor of retpoline and eIBRS on Intel chips, and the default Linux kernel mitigation on AMD systems - might be a viable option to close the newly discovered BHI security gap on Intel silicon.

In other words, AMD's Spectre v2 protection was found by Intel to be inadequate: malware could still infer privileged data on certain AMD systems when the LFENCE/JMP protection method is in place.

"While Spectre-BHB is similar to Spectre v2, the CSV2 hardware features introduced to mitigate against Spectre v2 do not work against Spectre-BHB," Arm explained in its whitepaper [PDF] on the subject.

News URL

https://go.theregister.com/feed/www.theregister.com/2022/03/15/spectre_bti_intel_amd_arm/