I-Qualcomm nayo isengozini, kungenzeka kukhishwe okhiye abazimele

Kokuthunyelwe kwangaphambilini sazisile ukuthi ama-chips I-Broadcom yayisengozini yokuhlaselwas futhi manje kulokhu abacwaningi abavela enkampanini INCC Group iveze imininingwane yokuba sengozini (I-CVE-2018-11976 ) kuma-chips eQualcomm, lokho ivumela ukunquma okuqukethwe okhiye bokubethela okuyimfihlo etholakala endaweni eseceleni yeQualcomm QSEE (Qualcomm Secure Execution Environment) enclave esekelwe ubuchwepheshe be-ARZ TrustZone.

Inkinga izibonakalisa kuma-SoC amaningi we-Snapdragon, kuma-Smartphones asuselwa ku-Android. Ukulungiswa kwenkinga sekuvele kufakiwe kusibuyekezo se-Ephreli Android kanye nezinguqulo ezintsha ze-firmware zezinhlamvu zeQualcomm.

I-Qualcomm ithathe isikhathi esingaphezu konyaka ukulungiselela isixazululo: Ekuqaleni, imininingwane ngobungozi yathunyelwa kuQualcomm ngoMashi 19, 2018.

Ubuchwepheshe be-ARM TrustZone bukuvumela ukuthi udale izindawo ezihlukanisiwe zezingxenyekazi zekhompuyutha ezihluke ngokuphelele ohlelweni olukhulu futhi zisebenze kumprosesa ohlukile osebenzisa uhlelo oluhlukile olukhethekile lokusebenza.

Inhloso enkulu yeTrustZone ukuhlinzeka ukwenziwa okukodwa kokuphatha okhiye bokubethela, ukuqinisekiswa kwe-biometric, idatha yokukhokha nolunye ulwazi oluyimfihlo.

Ukusebenzisana nohlelo olusebenzayo lwenzeka ngokungaqondile ngokusebenzisa isikhombimsebenzisi sokuthumela.

Okhiye bokubethela okuyimfihlo babekwa ngaphakathi kwesitolo esikhiye se-Hardware, uma, uma senziwe kahle, sivimbela ukuthi singaputshuki uma uhlelo oluyisisekelo lusengozini.

Mayelana nenkinga

Ukuba sengozini kuhlotshaniswa nokwehluleka ekusebenzeni ye-algorithm yokucubungula ama-elliptic curves, okuholele ekuvuzeni kolwazi mayelana nokusebenza kwedatha.

Abaphenyi sebethuthukile inqubo yokuhlasela evela eceleni evumela, ngokususelwa ekuvuza okungaqondile, rthola okuqukethwe okhiye abayimfihlos etholakala kwi-Android Keystore ehlukaniswe ngehardware.

Ukuvuza kunqunywa ngokususelwa ekuhlaziyweni komsebenzi wezinguquko zebhulokhi yokubikezela kanye nezinguquko esikhathini sokufinyelela kudatha kwimemori.

Ngesikhathi sokuhlolwa, Abaphenyi bakhombisa ngempumelelo ukuvuselelwa kwezikhiye ezingama-224- kanye nama-256-bit ECDSA kusuka esitolo sokhiye esizimele kuzingxenyekazi zekhompuyutha ezisetshenziswe ku-Nexus 5X smartphone.

Ukubuyisa ukhiye, kuthathe cishe amasiginesha ayi-12 wedijithali ukukhiqiza, okuthathe amahora angaphezu kuka-14 ukuthi kuqedwe. Ithuluzi lamathuluzi leCachegrab lasetshenziselwa ukwenza lokhu kuhlasela.

Imbangela enkulu yenkinga ukwaba izinto ezivamile zehadiwe kanye nenqolobane yekhompyutha kuTrustZone nakuhlelo lokusingathwa: ukuhlukaniswa kwenziwa ezingeni lokwehlukaniswa okunengqondo, kepha ngokusebenzisa amabhulokhi wekhompyutha ajwayelekile nokusetha imikhondo yokubala nolwazi mayelana nokugxuma amakheli ku-cache cache ejwayelekile.

Usebenzisa indlela ye-Prime + Probe, ngokususelwa ekulinganiselweni koshintsho esikhathini sokufinyelela kulwazi olufakwe kunqolobane, ungabheka ukutholakala kwamaphethini athile kunqolobane ngokunemba okuphezulu ngokwanele kwemifudlana yedatha kanye nezimpawu zokwenza ikhodi ezihlobene nesiginesha yedijithali izibalo ku-TrustZone.

Isikhathi esiningi sokukhiqizwa kwesiginesha yedijithali enokhiye be-ECDSA kuma-chips eQualcomm sichithwa ekwenzeni imisebenzi yokuphindaphinda ku-loop kusetshenziswa i-vector yokuqalisa engashintshiwe (nonce) kusiginesha ngayinye.

Si umhlaseli angathola okungenani izingcezu ezimbalwa ngolwazi ngale vector, kungenzeka ukwethula ukuhlaselwa ekubuyiseleni ngokulandelana kwawo wonke ukhiye oyimfihlo.

Endabeni yeQualcomm, amaphuzu amabili okuvuza kwalolu lwazi avezwe ku-algorithm yokuphindaphinda: lapho kwenziwa ukubheka kwetafula nakwikhodi yokukhipha idatha enemibandela ngokususelwa kunani lebhithi lokugcina ku-vector "nonce".

Yize ikhodi yeQualcomm iqukethe izinyathelo zokumelana nokuvuza kolwazi eziteshini ezivela eceleni, indlela yokuhlasela esetshenzisiwe ikuvumela ukuthi weqe lezi zinyathelo futhi uchaze ezinye izingcezu zenani le- "nonce", elanele ukubuyisa izingcezu zokhiye ezingama-256 ze-ECDSA.