Uma vulnerabilidade foi identificada no n\u00facleo do Linux (CVE-2022-42896), que pode ser potencialmente explorada para executar c\u00f3digo remotamente no n\u00edvel do n\u00facleo ao enviar um pacote L2CAP formatado de forma espec\u00edfica via Bluetooth. Al\u00e9m disso, outro problema semelhante (CVE-2022-42895) foi encontrado no manipulador L2CAP, que pode levar ao vazamento de conte\u00fado da mem\u00f3ria do n\u00facleo em pacotes com informa\u00e7\u00f5es de configura\u00e7\u00e3o. A primeira vulnerabilidade existe desde agosto de 2014 (n\u00facleo 3.16) e a segunda desde outubro de 2011 (n\u00facleo 3.0). As vulnerabilidades foram corrigidas nas vers\u00f5es do n\u00facleo Linux 6.1.0, 6.0.8, 4.9.333, 4.14.299, 4.19.265, 5.4.224, 5.10.154 e 5.15.78. Voc\u00ea pode acompanhar a corre\u00e7\u00e3o nas distribui\u00e7\u00f5es nas seguintes p\u00e1ginas: Debian, Ubuntu, Gentoo, RHEL, SUSE, Fedora, Arch. <\/p>\n
Para demonstrar a possibilidade de um ataque remoto, foram publicados prot\u00f3tipos de exploits que funcionam no Ubuntu 22.04. Para realizar o ataque, o invasor deve estar dentro do alcance do Bluetooth \u2014 a emparelhamento pr\u00e9vio n\u00e3o \u00e9 necess\u00e1rio, mas o Bluetooth deve estar ativado no computador. Para o ataque, \u00e9 suficiente conhecer o endere\u00e7o MAC do dispositivo da v\u00edtima, que pode ser determinado por sniffing ou, em alguns dispositivos, calculado com base no endere\u00e7o MAC do Wi-Fi. <\/p>\n
A primeira vulnerabilidade (CVE-2022-42896) \u00e9 causada por uma refer\u00eancia a uma \u00e1rea de mem\u00f3ria j\u00e1 liberada (use-after-free) na implementa\u00e7\u00e3o das fun\u00e7\u00f5es l2cap_connect e l2cap_le_connect_req \u2014 ap\u00f3s a cria\u00e7\u00e3o do canal atrav\u00e9s da chamada de retorno new_connection, nenhuma trava era definida para ele, mas um temporizador (__set_chan_timer) era configurado, que ao expirar chama a fun\u00e7\u00e3o l2cap_chan_timeout e limpa o canal sem verificar se o trabalho com o canal foi conclu\u00eddo nas fun\u00e7\u00f5es l2cap_le_connect*. <\/p>\n
Por padr\u00e3o, o tempo limite \u00e9 de 40 segundos e suponha-se que uma condi\u00e7\u00e3o de corrida n\u00e3o pode ocorrer com esse atraso, mas foi descoberto que, devido a outro erro no manipulador SMP, \u00e9 poss\u00edvel provocar uma chamada instant\u00e2nea do temporizador, resultando em uma condi\u00e7\u00e3o de corrida. O problema em l2cap_le_connect_req pode levar ao vazamento de mem\u00f3ria do n\u00facleo, enquanto em l2cap_connect pode resultar na sobrescri\u00e7\u00e3o do conte\u00fado da mem\u00f3ria e execu\u00e7\u00e3o do c\u00f3digo do invasor. O primeiro tipo de ataque pode ser realizado usando Bluetooth LE 4.0 (desde 2009), enquanto o segundo pode ser realizado com Bluetooth BR\/EDR 5.2 (desde 2020). <\/p>\n
A segunda vulnerabilidade (CVE-2022-42895) \u00e9 causada pelo vazamento de dados residuais da mem\u00f3ria na fun\u00e7\u00e3o l2cap_parse_conf_req, o que pode ser usado para obter remotamente informa\u00e7\u00f5es sobre ponteiros para estruturas do n\u00facleo atrav\u00e9s do envio de solicita\u00e7\u00f5es de configura\u00e7\u00e3o especialmente formatadas. Na fun\u00e7\u00e3o l2cap_parse_conf_req, foi utilizada a estrutura l2cap_conf_efs, para a qual n\u00e3o foi realizada a inicializa\u00e7\u00e3o pr\u00e9via da mem\u00f3ria alocada e, atrav\u00e9s da manipula\u00e7\u00e3o do sinalizador FLAG_EFS_ENABLE, era poss\u00edvel incluir no pacote dados antigos da pilha. O problema se manifesta apenas em sistemas onde o n\u00facleo \u00e9 compilado com a op\u00e7\u00e3o CONFIG_BT_HS (desativada por padr\u00e3o, mas ativada em algumas distribui\u00e7\u00f5es, como Ubuntu). Para um ataque bem-sucedido, tamb\u00e9m \u00e9 necess\u00e1rio definir o par\u00e2metro HCI_HS_ENABLED por meio da interface de controle como verdadeiro (n\u00e3o utilizado por padr\u00e3o). \u0412 \u044f\u0434\u0440\u0435 Linux \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (CVE-2022-42896), \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0442\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u044c\u0441\u044f \u0434\u043b\u044f \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e\u0433\u043e \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u043a\u043e\u0434\u0430 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 \u044f\u0434\u0440\u0430 \u0447\u0435\u0440\u0435\u0437 \u043e\u0442\u043f\u0440\u0430\u0432\u043a\u0443 \u0441\u043f\u0435\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u043e\u0444\u043e\u0440\u043c\u043b\u0435\u043d\u043d\u043e\u0433\u043e L2CAP-\u043f\u0430\u043a\u0435\u0442\u0430 \u0447\u0435\u0440\u0435\u0437 Bluetooth. \u041a\u0440\u043e\u043c\u0435 \u0442\u043e\u0433\u043e, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0435\u0449\u0451 \u043e\u0434\u043d\u0430 \u043f\u043e\u0445\u043e\u0436\u0430\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 (CVE-2022-42895) \u0432 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0435 L2CAP, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043c\u043e\u0436\u0435\u0442 \u043f\u0440\u0438\u0432\u0435\u0441\u0442\u0438 \u043a \u0443\u0442\u0435\u0447\u043a\u0435 \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0433\u043e \u043f\u0430\u043c\u044f\u0442\u0438 \u044f\u0434\u0440\u0430 \u0432 \u043f\u0430\u043a\u0435\u0442\u0430\u0445 \u0441\u043e \u0441\u0432\u0435\u0434\u0435\u043d\u0438\u044f\u043c\u0438 \u043e \u043a\u043e\u043d\u0444\u0438\u0433\u0443\u0440\u0430\u0446\u0438\u0438. \u041f\u0435\u0440\u0432\u0430\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u0441 \u0430\u0432\u0433\u0443\u0441\u0442\u0430 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-106088","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\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\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Vulnerabilidades no n\u00facleo Linux, exploradas remotamente via Bluetooth | ProHoster","description":"Uma vulnerabilidade foi identificada no n\u00facleo Linux (CVE-2022-42896), que pode ser potencialmente explorada para executar c\u00f3digo remotamente no n\u00edvel do n\u00facleo atrav\u00e9s do envio de um pacote L2CAP especialmente formatado.","canonical_url":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-yadre-linux-udalyonno-ekspluatiruemye-cherez-bluetooth","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"pt_PT","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\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u0432 \u044f\u0434\u0440\u0435 Linux, \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0438\u0440\u0443\u0435\u043c\u044b\u0435 \u0447\u0435\u0440\u0435\u0437 Bluetooth | ProHoster","og:description":"\u0412 \u044f\u0434\u0440\u0435 Linux \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (CVE-2022-42896), \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0442\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u044c\u0441\u044f \u0434\u043b\u044f \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e\u0433\u043e \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u043a\u043e\u0434\u0430 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 \u044f\u0434\u0440\u0430 \u0447\u0435\u0440\u0435\u0437 \u043e\u0442\u043f\u0440\u0430\u0432\u043a\u0443 \u0441\u043f\u0435\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u043e\u0444\u043e\u0440\u043c\u043b\u0435\u043d\u043d\u043e\u0433\u043e L2CAP-\u043f\u0430\u043a\u0435\u0442\u0430 \u0447\u0435\u0440\u0435\u0437.","og:url":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-yadre-linux-udalyonno-ekspluatiruemye-cherez-bluetooth","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":"2022-12-15T11:06:35+00:00","article:modified_time":"2022-12-15T11:06:35+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":[],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/106088","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/comments?post=106088"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/106088\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media?parent=106088"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/categories?post=106088"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/tags?post=106088"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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Fonte: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"