Danieri Antonioli, muongorori wezvekuchengetedza weBluetooth uyo akambogadzira BIAS, BLUR, uye KNOB maitiro ekurwisa, aona huviri hutsva hwekusagadzikana (CVE-2023-24023) mune yeBluetooth chikamu chekutaurirana. Kusagadzikana uku kunokanganisa mashandisirwo ese eBluetooth anotsigira "Secure Connections" uye "Chengetedza Nyore Pairing" modhi, sekutsanangurwa kwazvinoitwa muBluetooth Core 4.2-5.4. Kuratidza mashandisiro anoshanda ekusagadzikana uku, misiyano mitanhatu yekurwisa yakagadziridzwa inobvumira kuvhiringa hukama pakati pemidziyo yakambopetwa yeBluetooth. Iyo kodhi yekushandisa nzira dzekurwisa uye maturusi ekuyedza kusarongeka zvakaburitswa paGitHub.
Kusagadzikana kwakaonekwa panguva yekuongororwa kwemaitiro ekumberi uye emunguva yemberi ekuvanzika, ayo anodzivirira kukanganisa makiyi echikamu kana kiyi inoenderera ichitemerwa (kukanganisa imwe yemakiyi anoramba aripo hakufanire kukonzeresa kudhiropiwa kwezvakambobvumwa kana zveramangwana zvikamu) uye chikamu chekushandisazve kiyi (kiyi kubva kune imwe chikamu haifanirwe kushanda kune imwe chikamu). Kusagadzikana kwakaonekwa kunobvumira kudarika chengetedzo iyi uye kushandisazve isina kuchengeteka kiyi muzvikamu zvakasiyana. Kusagadzikana kunokonzerwa nekukanganisa kweiyo base chiyero, haina kunangana kune yega Bluetooth stacks, uye inoratidzira mumachipi kubva kune vakasiyana vagadziri.
Nzira dzekurwisa dzakarongwa dzinoshandisa nzira dzakasiyana-siyana dzekubiridzira dzekirasi (LSC, Legacy Secure Connections zvichibva pane legacy cryptographic primitives) uye yakachengeteka (SC, Secure Connections yakavakirwa paECDH neAES-CCM) Bluetooth yekubatanidza pakati peiyo system uye peripheral mudziyo, pamwe nekurwiswa kwemurume-mukati-yepakati pakubatanidza muLSC uye SC modhi. Zvinofungidzirwa kuti ese maBluetooth mashandisirwo anoenderana neyakajairwa anotapukirwa neimwe vhezheni yekurwiswa kweBLUFFS. Iyo nzira yakaratidzwa pamidziyo gumi nemasere kubva kumakambani anosanganisira Intel, Broadcom, Apple, Google, Microsoft, CSR, Logitech, Infineon, Bose, Dell, uye Xiaomi.
Chinhu chekusagadzikana chinodzika kusvika pakukwanisa, pasina kutyora chiyero, kumanikidza kubatana kushandisa yekare LSC modhi uye isingavimbike pfupi yechikamu kiyi (SK), nekutsanangura iyo shoma inogoneka entropy panguva yekubatanidza kutaurirana maitiro uye kusateera zvirimo mumhinduro neathentication parameters (CR), iyo inotungamira kuchizvarwa chenguva dzose parameter SK (inogara ichiverengerwa chikamu chechikamu SK) kiyi (PK) uye zvimiro zvakabvumiranwa panguva yechirongwa). Semuyenzaniso, panguva yekurwiswa kweMITM, munhu anorwisa anogona kutsiva maparamendi 𝐴𝐶 uye 𝑆𝐷 ne zero kukosha panguva yechikamu chekukurukurirana maitiro, uye kuseta iyo entropy 𝑆𝐸 kusvika 1, izvo zvinozotungamira mukuumbwa kwechikamu kiyi 𝑆𝐾 (iyo chiyero cheiyo 1 ente ne7 (56 bits), iyo inofananidzwa maererano nekuvimbika kune kusarudzwa kweDES makiyi).
Kana munhu anorwisa akabudirira kuwana kiyi ipfupi munguva yenhaurirano yekubatanidza, vanogona kuzoshandisa chisimba kuona kiyi inoenderera (PK) inoshandiswa kuvharidzira nekudzima traffic pakati pemidziyo. Sezvo kurwiswa kweMITM kuchigona kutanga kushandiswa kwekiyi yekuvharidzira imwechete, kana kiyi iyi yakamanikidzwa, inogona kushandiswa kubvisa zvese zvakapfuura uye zvenguva yemberi zvakabvumwa neanorwisa.
Kudzikamisa kusadzivirirwa, muongorori akakurudzira shanduko kune chiyero chinowedzera LMP protocol uye kushandura pfungwa yekushandisa Key Derivation Function (KDF) paunenge uchigadzira makiyi muLSC modhi. Shanduko iyi haiparadze kuenderana kumashure, asi inoda kuisirwa murairo weLMP wakawedzerwa uye kukosha kwekutumira mamwe 48 bytes. Iyo Bluetooth SIG, sangano rinoita basa rekugadzira mazinga eBluetooth, yakurudzira kuramba yakavharidzirwa chiteshi chekubatanidza nemakiyi anosvika 7 bytes seyekuchengetedza. Mashandisirwo anogara achishandisa Chengetedzo Mode 4 Level 4 anokurudzirwa kuramba kubatana nemakiyi anosvika gumi nematanhatu bytes.
Source: opennet.ru
