Tawagar masu bincike daga jami'o'in Amurka da dama sun kirkiri sabuwar dabarar kai hari ta hanyar tasha wacce zata basu damar sake gina bayanan gani da GPU ke sarrafa su. Yin amfani da hanyar da aka tsara, wanda ake yiwa lakabi da GPU.zip, maharin zai iya tantance bayanan da aka nuna akan allon. Daga cikin wasu abubuwa, ana iya kai harin ta hanyar mashigin yanar gizo. Alal misali, an nuna yadda shafin yanar gizon da aka buɗe a cikin Chrome zai iya samun bayanai game da pixels da aka nuna yayin yin wani shafin yanar gizon da aka bude a cikin mazugi ɗaya.
Tushen zubin bayanin shine haɓakawa da aka yi amfani da shi a cikin GPUs na zamani wanda ke ba da damar damfara bayanan hoto. Batun yana bayyana kanta lokacin da aka kunna matsawa akan duk haɗaɗɗen GPUs (AMD, Apple, ARM, Intel, Qualcomm) da katunan zane-zane na NVIDIA masu hankali. Masu bincike sun gano cewa haɗaɗɗen Intel da AMD GPUs koyaushe suna ba da damar matse bayanan hoto, koda lokacin aikace-aikacen ba sa buƙatar wannan haɓaka ta musamman. Wannan matsawa yana haifar da zirga-zirgar zirga-zirgar DRAM da nauyin cache wanda ya dace da yanayin bayanan da ake sarrafa, wanda za'a iya sake gina pixel-by-pixel ta hanyar nazarin tashoshi na gefe.
Hanyar tana da sannu a hankali. Misali, akan tsarin da aka haɗa AMD Ryzen 7 4800U GPU, harin don tantance sunan mai amfani wanda a ƙarƙashinsa mai amfani ya shiga Wikipedia a wani shafin ya ɗauki mintuna 30 kuma ya samar da abun ciki na pixel tare da daidaiton 97%. A kan tsarin tare da haɗin gwiwar Intel i7-8700 GPU, irin wannan harin ya ɗauki mintuna 215 tare da daidaito 98%.
A yayin harin da aka yi tushen burauza, gidan yanar gizon da aka yi niyya yana buɗewa a keke-da-keke a cikin iframe don fara nunawa. Don tantance bayanan da za a nunawa, ana juyar da fitarwar iframe zuwa wakilcin launin toka, wanda ake amfani da matatar SVG. Wannan tace bi-da-bi yana amfani da abin rufe fuska waɗanda ke yin kuma baya gabatar da matsi mai mahimmanci. Dangane da canjin lokacin bayarwa na samfuran tunani, ana gano gaban duhu ko haske a wani takamaiman wuri. An sake gina hoton gaba ɗaya ta hanyar duban pixel-by-pixel na jeri ta amfani da waɗannan mashin.
An sanar da GPU da dillalan burauza game da batun a cikin Maris, amma har yanzu babu wani dillali da ya ƙirƙira faci, saboda yuwuwar harin a ƙarƙashin yanayin da bai dace ba yana da shakka kuma batun yana da fifiko na ka'ida. Har yanzu Google bai yanke shawara ko zai toshe harin a matakin burauzar Chrome ba. Chrome yana da rauni saboda yana ba da damar iframes daga wasu rukunin yanar gizon su yi lodi ba tare da share kukis ba, yana ba da damar yin amfani da tacewa na SVG akan iframes, da wakilai masu ba da GPU. Firefox da Safari ba su da rauni saboda ba su cika waɗannan sharuɗɗan ba. Har ila yau harin ba ya shafi shafukan da ke hana sakawa ta hanyar iframes a wasu rukunin yanar gizo (misali, ta hanyar saita taken X-Frame-Options HTTP zuwa "SAMEORIGIN" ko "DENY," ko ta hanyar daidaita hanyar shiga ta amfani da taken-Tsaro-Tsaro-Policy header).
source: budenet.ru
