AMD tuam txhab hais txog kev ua haujlwm ntawm kev kho cov kev tsis sib haum xeeb ""(CVE-2020-12890), uas tso cai rau koj kom tau txais kev tswj hwm ntawm UEFI firmware thiab ua tiav cov cai ntawm SMM (System Management Mode) qib. Kev tawm tsam yuav tsum muaj kev nkag mus rau lub cev rau cov khoom siv lossis nkag mus rau qhov system nrog cov cai tswj hwm. Nyob rau hauv cov ntaub ntawv ntawm kev ua tiav kev tawm tsam, tus neeg tawm tsam tuaj yeem siv lub interface (AMD Generic Encapsulated Software Architecture) kom ua tiav cov cai tsis raug cai uas tsis tuaj yeem tshwm sim los ntawm kev ua haujlwm.
Vulnerabilities muaj nyob rau hauv cov cai suav nrog hauv UEFI firmware, ua tiav hauv (Ntiv nplhaib -2), uas muaj qhov tseem ceeb dua li hypervisor hom thiab tiv thaiv lub nplhaib xoom, thiab muaj kev txwv tsis pub nkag mus rau txhua qhov system nco. Piv txwv li, tom qab tau txais kev nkag mus rau OS los ntawm kev siv lwm qhov tsis zoo lossis kev tsim vaj tsev sib raug zoo, tus neeg tawm tsam tuaj yeem siv SMM Callout vulnerabilities los hla UEFI Secure Boot, txhaj tshuaj tiv thaiv kab mob tsis pom lossis cov hauv paus hauv SPI Flash, thiab tseem tso tawm kev tawm tsam. ntawm hypervisors los hla cov txheej txheem rau kev tshuaj xyuas kev ncaj ncees ntawm ib puag ncig virtual.
Qhov tsis zoo yog tshwm sim los ntawm qhov yuam kev hauv SMM code vim tsis muaj kev kuaj xyuas lub hom phiaj tsis nyob thaum hu rau SmmGetVariable() ua haujlwm hauv 0xEF SMI handler. Cov kab no tuaj yeem tso cai rau tus neeg tawm tsam sau cov ntaub ntawv tsis txaus ntseeg rau SMM sab hauv nco (SMRAM) thiab khiav nws raws li cov cai nrog SMM cov cai. Raws li cov ntaub ntawv ua ntej, qhov teeb meem tshwm sim hauv qee qhov APUs (AMD Fusion) rau cov neeg siv khoom thiab cov khoom siv tsim los ntawm 2016 txog 2019. AMD twb tau muab cov tuam txhab motherboard feem ntau nrog cov firmware hloov tshiab uas kho qhov teeb meem, thiab qhov hloov tshiab tau npaj yuav xa mus rau cov tuam txhab tseem tshuav nyob rau lub hli tas los.
Tau qhov twg los: opennet.ru