Boka revatsvagiri kubva kuGraz University of Technology (Austria), yaimbozivikanwa nekugadzira iyo MDS, NetSpectre, Throwhammer uye ZombieLoad kurwiswa, yakaburitsa ruzivo rwekutsva kwedivi-chiteshi kurwisa (CVE-2021-46778) pa AMD processor scheduler queue. , inoshandiswa kuronga kuitiswa kwemirairo muzvikamu zvakasiyana zvekuuraya zveCPU. Kurwiswa uku, kunonzi SQUIP, kunokubvumidza kuti uone iyo data inoshandiswa mukuverenga mune imwe nzira kana chaiyo muchina kana kuronga yakavanzika yekutaurirana chiteshi pakati pemaitiro kana chaiwo michina inobvumidza iwe kuchinjanisa data nekupfuura masisitimu ekudzora nzira.
AMD CPUs yakavakirwa pa2000st, 5000nd, uye 3000rd chizvarwa Zen microarchitectures (AMD Ryzen XNUMX-XNUMX, AMD Ryzen Threadripper, AMD Athlon XNUMX, AMD EPYC) inokanganiswa kana uchishandisa Simultaneous Multithreading Technology (SMT). Intel processors haibatike kurwisa, sezvo vachishandisa imwe chete scheduler queue, nepo vari panjodzi AMD processors vanoshandisa mitsara yakaparadzana kune yega yega yekuuraya unit. Sechishandiso chekuvharisa kuburitswa kweruzivo, AMD yakakurudzira kuti vanogadzira vashandise maalgorithms anogara achiita masvomhu nguva dzose, zvisinei nemhando yedata riri kugadziriswa, uye zvakare kudzivirira kuchinjika kwakavakirwa pane zvakavanzika data.
Kurwiswa kwacho kunobva pakuongororwa kwechiyero chekukakavadzana (nhanho yekukakavadzana) mumitsetse yakasiyana-siyana uye inoitwa kuburikidza nekuyerwa kwekunonoka kana uchitanga macheki mavhisi akaitwa mune imwe tambo yeSMT pane imwechete yemuviri CPU. Kuongorora zvirimo, iyo Prime + Probe nzira yakashandiswa, izvo zvinoreva kuzadza mutsara nereferensi seti yezvinokosha uye kuona shanduko nekuyera nguva yekuwana kwavari paunenge uchizadza.
Munguva yekuedza, vatsvakurudzi vakakwanisa kunyatsogadzirisa yakavanzika 4096-bit RSA kiyi yakashandiswa kugadzira masiginecha edhijitari vachishandisa mbedTLS 3.0 cryptographic library, iyo inoshandisa iyo Montgomery algorithm kusimudza nhamba kune simba modulo. Zvakatora 50500 traces kuona kiyi. Nguva yese yekurwisa yakatora maminetsi makumi matatu nemasere. Misiyano yekurwisa inoratidzwa inopa kuvuza pakati pemaitiro akasiyana uye chaiwo michina inodzorwa neKVM hypervisor. Inoratidzwawo kuti nzira yacho inogona kushandiswa kuronga kuendesa data yakavanzika pakati pemashini chaiwo pachiyero che 38 Mbit / s uye pakati pemaitiro pachiyero che 0.89 Mbit / s ine chikanganiso chisingasviki 2.70%.
Source: opennet.ru