AMD banyere ịrụ ọrụ na idozi usoro adịghị ike""(CVE-2020-12890), nke na-enye gị ohere ijikwa firmware UEFI wee mebie koodu na ọkwa SMM (System Management Mode). Mwakpo chọrọ ịnweta akụrụngwa ma ọ bụ ịnweta sistemụ nwere ikike nchịkwa. Ọ bụrụ na mwakpo gara nke ọma, onye mwakpo ahụ nwere ike iji interface ahụ (AMD Generic Encapsulated Software Architecture) iji mebie koodu aka ike nke enweghị ike ikpughe site na sistemụ arụmọrụ.
Ọdịmma dị na koodu etinyere na firmware UEFI, nke etinyere na ya (Mgbanaka -2), nke nwere mkpa dị elu karịa ọnọdụ hypervisor na mgbanaka mgbanaka efu, ma nwee ohere na-enweghị njedebe na ebe nchekwa sistemụ niile. Dịka ọmụmaatụ, mgbe ị nwetasịrị OS n'ihi iji adịghị ike ndị ọzọ ma ọ bụ usoro injinia mmekọrịta ọha na eze, onye na-awakpo nwere ike iji SMM Callout adịghị ike gafere UEFI Secure Boot, tinye koodu ọjọọ na-adịghị ahụ anya ma ọ bụ rootkits n'ime SPI Flash, wee malite ọgụ. na hypervisors ka ị gafere usoro maka ịlele iguzosi ike n'ezi ihe nke gburugburu mebere.
A na-ebute adịghị ike ndị ahụ site na mperi dị na koodu SMM n'ihi enweghị ịlele adreesị nke ebe nchekwa ihe mgbe ị na-akpọ ọrụ SmmGetVariable() na onye njikwa 0xEF SMI. Ahụhụ a nwere ike ikwe ka onye na-awakpo dee data aka ike na ebe nchekwa ime SMM (SMRAM) wee mee ya dị ka koodu nwere ikike SMM. Dabere na data mbido, nsogbu a na-apụta na ụfọdụ APUs (AMD Fusion) maka ndị ahịa na sistemụ agbakwunyere sitere na 2016 ruo 2019. AMD enyelarị ọtụtụ ndị na-emepụta motherboard nwelite firmware nke na-edozi nsogbu ahụ, a na-eme atụmatụ iziga mmelite ahụ na ndị na-emepụta ihe fọdụrụ na njedebe nke ọnwa.
isi: opennet.ru