{"id":100281,"date":"2021-05-26T04:22:47","date_gmt":"2021-05-26T02:22:48","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/novaya-tehnika-ataki-rowhammer-na-dram-pamyat"},"modified":"2021-05-26T04:22:47","modified_gmt":"2021-05-26T02:22:48","slug":"novaya-tehnika-ataki-rowhammer-na-dram-pamyat","status":"publish","type":"post","link":"https:\/\/prohoster.info\/ro\/blog\/news\/novaya-tehnika-ataki-rowhammer-na-dram-pamyat","title":{"rendered":"Noua tehnic\u0103 de atac RowHammer asupra memoriei DRAM","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Compania Google a prezentat \u201eHalf-Double\u201d, o nou\u0103 tehnic\u0103 de atac din cadrul clasei RowHammer, care permite modificarea con\u021binutului unor bi\u021bi individuali din memoria dinamic\u0103 de acces aleator (DRAM). Atacul este replicabil pe unele dintre chipurile DRAM moderne, ale c\u0103ror produc\u0103tori au reu\u0219it s\u0103 reduc\u0103 geometria celulelor. <\/p>\n

Reamintim c\u0103 atacurile de tip RowHammer permit distorsionarea con\u021binutului unor bi\u021bi din memorie prin citirea ciclic\u0103 a datelor din celulele de memorie adiacente. Deoarece memoria DRAM reprezint\u0103 un aranjament bidimensional al celulelor, fiecare dintre ele const\u00e2nd dintr-un condensator \u0219i un transistor, efectuarea unei citiri continue asupra acelea\u0219i zone de memorie duce la fluctua\u021bii de tensiune \u0219i anomalii care provoac\u0103 o mic\u0103 pierdere de sarcin\u0103 \u00een celulele \u00eenvecinate. Dac\u0103 intensitatea citirii este suficient de mare, celula adiacent\u0103 poate pierde o cantitate semnificativ\u0103 de sarcin\u0103, iar ciclul de regenerare ulterior nu reu\u0219e\u0219te s\u0103 restabileasc\u0103 starea ini\u021bial\u0103, conduc\u00e2nd la modificarea valorii stocate \u00een celul\u0103. <\/p>\n

Pentru a se proteja \u00eempotriva RowHammer, produc\u0103torii de chipuri au implementat mecanismul TRR (Target Row Refresh), care protejeaz\u0103 \u00eempotriva distorsiunii celulelor din r\u00e2ndurile adiacente. Metoda Half-Double permite ocolirea acestei protec\u021bii, manipul\u00e2nd faptul c\u0103 distorsiunile nu sunt limitate la r\u00e2ndurile adiacente \u0219i se extind la alte r\u00e2nduri de memorie, de\u0219i \u00eentr-o m\u0103sur\u0103 mai mic\u0103. Inginerii Google au demonstrat c\u0103 pentru r\u00e2ndurile de memorie \u201eA\u201d, \u201eB\u201d \u0219i \u201eC\u201d, este posibil s\u0103 ataci r\u00e2ndul \u201eC\u201d \u00een timpul unui acces foarte intens la r\u00e2ndul \u201eA\u201d \u0219i cu o activitate redus\u0103, care implic\u0103 r\u00e2ndul \u201eB\u201d. Acces\u0103rile la r\u00e2ndul \u201eB\u201d \u00een timpul atacului activeaz\u0103 o scurgere neliniar\u0103 de sarcini \u0219i permit utilizarea r\u00e2ndului \u201eB\u201d ca mijloc de transport pentru a transmite efectul Rowhammer de la r\u00e2ndul \u201eA\u201d la \u201eC\u201d.

\"Noua<\/center> <\/p>\n

Spre deosebire de atacul TRRespass, care manipuleaz\u0103 neajunsurile din diferitele implement\u0103ri ale mecanismului de prevenire a distorsion\u0103rii celulelor, atacul Half-Double se bazeaz\u0103 pe propriet\u0103\u021bile fizice ale substratului de siliciu. Half-Double arat\u0103 c\u0103 efectele care conduc la Rowhammer sunt probabil o caracteristic\u0103 a distan\u021bei, nu a apropierii directe a celulelor. Pe m\u0103sur\u0103 ce geometria celulelor din chipseturile moderne se mic\u0219oreaz\u0103, raza de influen\u021b\u0103 a distorsiunilor cre\u0219te. Nu este exclus ca efectul s\u0103 fie observat la o distan\u021b\u0103 de mai mult de dou\u0103 r\u00e2nduri. <\/p>\n

Se remarc\u0103 faptul c\u0103, \u00eempreun\u0103 cu asocia\u021bia JEDEC, au fost elabora\u021bi mai multe propuneri cu analiza unor posibile c\u0103i de blocare a acestor atacuri. Informa\u021biile despre metod\u0103 au fost dezv\u0103luite, deoarece Google consider\u0103 c\u0103 cercetarea realizat\u0103 extinde semnificativ \u00een\u021belegerea fenomenului Rowhammer \u0219i subliniaz\u0103 importan\u021ba cooper\u0103rii \u00eentre cercet\u0103tori, produc\u0103tori de cipuri \u0219i alte p\u0103r\u021bi interesate \u00een dezvoltarea unei solu\u021bii complete \u0219i pe termen lung pentru protec\u021bie.
\n
Sursa: opennet.ro<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u041a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Google \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u043b\u0430 «Half-Double», \u043d\u043e\u0432\u0443\u044e \u0442\u0435\u0445\u043d\u0438\u043a\u0443 \u0430\u0442\u0430\u043a \u043a\u043b\u0430\u0441\u0441\u0430 RowHammer, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0438\u0437\u043c\u0435\u043d\u0438\u0442\u044c \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0435 \u043e\u0442\u0434\u0435\u043b\u044c\u043d\u044b\u0445 \u0431\u0438\u0442\u043e\u0432 \u0434\u0438\u043d\u0430\u043c\u0438\u0447\u0435\u0441\u043a\u043e\u0439 \u043e\u043f\u0435\u0440\u0430\u0442\u0438\u0432\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438 (DRAM). \u0410\u0442\u0430\u043a\u0430 \u0432\u043e\u0441\u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0441\u044f \u043d\u0430 \u043d\u0435\u043a\u043e\u0442\u043e\u0440\u044b\u0445 \u0441\u043e\u0432\u0440\u0435\u043c\u0435\u043d\u043d\u044b\u0445 \u0447\u0438\u043f\u0430\u0445 DRAM, \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0438 \u043a\u043e\u0442\u043e\u0440\u044b\u0445 \u0434\u043e\u0431\u0438\u043b\u0438\u0441\u044c \u0443\u043c\u0435\u043d\u044c\u0448\u0435\u043d\u0438\u044f \u0433\u0435\u043e\u043c\u0435\u0442\u0440\u0438\u0438 \u044f\u0447\u0435\u0435\u043a. \u041d\u0430\u043f\u043e\u043c\u043d\u0438\u043c, \u0447\u0442\u043e \u0430\u0442\u0430\u043a\u0438 \u043a\u043b\u0430\u0441\u0441\u0430 RowHammer \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0442 \u0438\u0441\u043a\u0430\u0437\u0438\u0442\u044c \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0435 \u043e\u0442\u0434\u0435\u043b\u044c\u043d\u044b\u0445 \u0431\u0438\u0442\u043e\u0432 \u043f\u0430\u043c\u044f\u0442\u0438 \u043f\u0443\u0442\u0451\u043c \u0446\u0438\u043a\u043b\u0438\u0447\u043d\u043e\u0433\u043e \u0447\u0442\u0435\u043d\u0438\u044f \u0434\u0430\u043d\u043d\u044b\u0445 \u0438\u0437 \u0441\u043e\u0441\u0435\u0434\u043d\u0438\u0445 \u044f\u0447\u0435\u0435\u043a \u043f\u0430\u043c\u044f\u0442\u0438. \u0422\u0430\u043a \u043a\u0430\u043a \u043f\u0430\u043c\u044f\u0442\u044c DRAM \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":100282,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-100281","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Noua tehnic\u0103 de atac RowHammer asupra memoriei DRAM | ProHoster","description":"Compania Google a prezentat \"Half-Double\", o nou\u0103 tehnic\u0103 de atac din clasa RowHammer, care permite modificarea con\u021binutului anumitor bi\u021bi din memoria RAM dinamic\u0103 (DRAM).","canonical_url":"https:\/\/prohoster.info\/ro\/blog\/news\/novaya-tehnika-ataki-rowhammer-na-dram-pamyat","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"ro_RO","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u041d\u043e\u0432\u0430\u044f \u0442\u0435\u0445\u043d\u0438\u043a\u0430 \u0430\u0442\u0430\u043a\u0438 RowHammer \u043d\u0430 DRAM-\u043f\u0430\u043c\u044f\u0442\u044c | ProHoster","og:description":"\u041a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Google \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u043b\u0430 "Half-Double", \u043d\u043e\u0432\u0443\u044e \u0442\u0435\u0445\u043d\u0438\u043a\u0443 \u0430\u0442\u0430\u043a \u043a\u043b\u0430\u0441\u0441\u0430 RowHammer, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0438\u0437\u043c\u0435\u043d\u0438\u0442\u044c \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0435 \u043e\u0442\u0434\u0435\u043b\u044c\u043d\u044b\u0445 \u0431\u0438\u0442\u043e\u0432 \u0434\u0438\u043d\u0430\u043c\u0438\u0447\u0435\u0441\u043a\u043e\u0439 \u043e\u043f\u0435\u0440\u0430\u0442\u0438\u0432\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438 (DRAM).","og:url":"https:\/\/prohoster.info\/ro\/blog\/news\/novaya-tehnika-ataki-rowhammer-na-dram-pamyat","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2021-05-26T02:22:48+00:00","article:modified_time":"2021-05-26T02:22:48+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"100281","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":null,"breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-05-26 02:32:56","updated":"2022-09-30 15:38:37","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts\/100281","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/comments?post=100281"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts\/100281\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/media\/100282"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/media?parent=100281"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/categories?post=100281"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/tags?post=100281"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}