Qualcomm zvakare iri panjodzi, zvinokwanisika kutora zvakavanzika makiyi

Mune zvakapfuura zvinyorwa isu takazivisa kuti machipisi Broadcom vaive panjodzi yekurwiswas uye ikozvino nguva ino vaongorori vanobva kukambani NCC Boka rakaburitsa ruzivo rwekushushikana (CVE-2018-11976 ) pane Qualcomm machipisi, , que inobvumidza kuona izvo zvemukati zvakavanzika encryption kiyi iri mune yakasarudzika Qualcomm QSEE (Qualcomm Yakachengeteka Kuuraya Nzvimbo) enclave yakavakirwa paARZ TrustZone tekinoroji.

Dambudziko rinozviratidza mune dzakawanda Snapdragon SoCs, pane Android-based mafoni. Kugadziriswa kwedambudziko kwakatove kuverengerwa muna Kubvumbi Android kugadzirisa uye nyowani firmware vhezheni yeQualcomm machipisi.

Qualcomm yakatora rinopfuura gore kugadzirira mhinduro: Pakutanga, ruzivo nezve kushomeka rwakatumirwa kuQualcomm munaKurume 19, 2018.

ARM TrustZone tekinoroji inoita kuti iwe ugadzire yakachengetedzwa Hardware yakasarudzika nharaunda dzakanyatsopatsanuka kubva kune yakakosha system uye inomhanya pane yakasarudzika chaiyo processor uchishandisa yakasarudzika yakasarudzika sisitimu yekushandisa.

Chinangwa chikuru cheTrustZone ndechekupa kusarudzika kwekutora makiyi ekubata, biometric kuvimbiswa, data rekubhadhara uye rumwe ruzivo rwekuvanzika.

Kubatana neiyo huru yekushandisa system inoitika zvisina kunangana kuburikidza neiyo inotumira interface.

Yakavanzika yekuvhara makiyi anoiswa mukati mehardware yakasarudzika keystore iyo, kana ikaitwa nemazvo, inodzivirira kubva pakuburitswa kana iyo yepasi system yakanganiswa.

Nezve dambudziko

Iyo kushushikana inosanganiswa nekutadza mukuitwa yealgorithm yekugadzirisa elliptic curves, izvo zvakatungamira mukudonha kweruzivo nezve kugadziriswa kwedata.

Vatsvakurudzi vakagadzira yechitatu-bato kurwisa nzira iyo inobvumidza, Yakavakirwa pane zvisina kunanga kuvuza, rdzosa zvirimo zvemakiyi epachivandes iri mune yakasarudzika-yega Android Keystore.

Zvinodonhedza zvinotemerwa zvichibva pane ongororo yechiitiko chekufanotaura block block shanduko uye shanduko mukuwana nguva kune data mundangariro.

Munguva yekuyedza, Vatsvagiri vakabudirira kuratidza kudzoserwa kwemakiyi e224- uye 256-bit ECDSA kubva kuchitoro chakazvimiririra pane Hardware inoshandiswa muNexus 5X smartphone.

Kudzorera kiyi, zvakatora zvakapetwa zviuru gumi nezviviri zvemadhijitari kugadzira, izvo zvakatora anopfuura maawa gumi nemana kuti apedze. Cachegrab toolkit yakashandiswa kuita kurwisa.

Chikonzero chikuru chechinetso kugovana kwezvinhu zvakajairika zvemagetsi uye cache yekomputa muTrustZone uye muhurongwa hwevagashiri: kusarudzika kunoitwa padanho rekuparadzanisa zvine musoro, asi nekushandisa zvakajairika zvemakomputa mabhureki uye nekuisa matanho ekuverenga uye ruzivo nezve kusvetuka kero mune processor yakajairwa cache.

Uchishandisa iyo Prime + Probe nzira, zvichibva pakufungidzira kweshanduro yekuwana nguva kune ruzivo rwakachengetwa, unogona kutarisa kuwanikwa kwemamwe mapatani mune cache ine zvakakwana zvakakwana kuenzanisira kweta data uye zviratidzo zvekuuraya zvekodhi zvine chekuita nesiginicha yedhijitari. kuverenga muTrustZone.

Mazhinji edigital siginecha yekugadzira nguva neECDSA makiyi paQualcomm machipisi anoshandiswa kuita mashandiro ekuita chiuno uchishandisa chishandiso chisina kuchinjika chekutanga vector (nonce) yesiginicha yega yega.

Si anorwisa anogona kupora angangoita mashoma mabhii neruzivo nezve iyi vector, zvinokwanisika kuvhura kurwisa kwekuteedzana kudzoreredza iyo yega yakavanzika kiyi.

Panyaya yeQualcomm, mapoinzi maviri ekudonhedza ruzivo urwu rwakaratidzwa mune yekuwanza algorithm: kana uchiita tafura yekutarisa uye mune ine mamiriro mamiriro ekutora kodhi inoenderana nekukosha kweyekupedzisira bit mu "nonce" vector.

Kunyangwe iyo Qualcomm kodhi iine matanho ekumisidzana nekudonha kweruzivo mumatatu-bato nzira, yekurwisa nzira yakagadziriswa inokutendera iwe kupfuura idzi matanho uye kutsanangura mamwe mabheti eiyo "nonce" kukosha, iyo inokwana kudzorera 256 ECDSA kiyi mabits.