No m\u00f3dulo ksmbd, que inclui uma implementa\u00e7\u00e3o incorporada no n\u00facleo do Linux do servidor de arquivos baseado no protocolo SMB, foi identificada uma vulnerabilidade cr\u00edtica que permite a execu\u00e7\u00e3o remota de c\u00f3digo com privil\u00e9gios de n\u00facleo. O ataque pode ser realizado sem autentica\u00e7\u00e3o, desde que o m\u00f3dulo ksmbd esteja ativado no sistema. O problema foi detectado a partir do n\u00facleo 5.15, lan\u00e7ado em novembro de 2021, e foi corrigido nas atualiza\u00e7\u00f5es 5.15.61, 5.18.18 e 5.19.2, publicadas em agosto de 2022. Como o identificador CVE ainda n\u00e3o foi atribu\u00eddo ao problema, n\u00e3o h\u00e1 informa\u00e7\u00f5es exatas sobre a corre\u00e7\u00e3o nos pacotes de distribui\u00e7\u00e3o. <\/p>\n
Os detalhes da explora\u00e7\u00e3o da vulnerabilidade ainda n\u00e3o foram divulgados, sabe-se apenas que ela \u00e9 causada por uma refer\u00eancia a uma \u00e1rea de mem\u00f3ria j\u00e1 liberada (Use-After-Free) devido \u00e0 falta de verifica\u00e7\u00e3o da exist\u00eancia do objeto antes de realizar opera\u00e7\u00f5es com ele. O problema est\u00e1 relacionado ao fato de que na fun\u00e7\u00e3o smb2_tree_disconnect() a mem\u00f3ria alocada para a estrutura ksmbd_tree_connect foi liberada, mas ainda havia um ponteiro sendo utilizado na manipula\u00e7\u00e3o de determinadas solicita\u00e7\u00f5es externas que continham comandos SMB2_TREE_DISCONNECT. <\/p>\n
Al\u00e9m da vulnerabilidade mencionada no ksmbd, foram corrigidos 4 problemas menos graves: <\/p>\n
O suporte ao funcionamento do servidor SMB por meio do m\u00f3dulo ksmbd est\u00e1 inclu\u00eddo no pacote Samba, a partir da vers\u00e3o 4.16.0. Ao contr\u00e1rio do servidor SMB que opera no espa\u00e7o do usu\u00e1rio, o ksmbd \u00e9 mais eficiente em termos de desempenho, consumo de mem\u00f3ria e integra\u00e7\u00e3o com recursos avan\u00e7ados do n\u00facleo. O ksmbd \u00e9 apresentado como uma extens\u00e3o de alto desempenho e pronta para uso em dispositivos embarcados, integr\u00e1vel com as ferramentas e bibliotecas do Samba, se necess\u00e1rio. Os autores do c\u00f3digo ksmbd s\u00e3o Namjae Jeon da Samsung e Hyunchul Lee da LG, e a manuten\u00e7\u00e3o no n\u00facleo \u00e9 feita por Steve French da Microsoft, mantenedor do subsistema CIFS\/SMB2\/SMB3 no n\u00facleo Linux e membro de longa data da equipe de desenvolvedores do Samba, que fez uma contribui\u00e7\u00e3o significativa para a implementa\u00e7\u00e3o do suporte aos protocolos SMB\/CIFS no Samba e Linux. \u0412 \u043c\u043e\u0434\u0443\u043b\u0435 ksmbd, \u0432\u043a\u043b\u044e\u0447\u0430\u044e\u0449\u0435\u043c \u0432\u0441\u0442\u0440\u043e\u0435\u043d\u043d\u0443\u044e \u0432 \u044f\u0434\u0440\u043e Linux \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u044e \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 \u043d\u0430 \u0431\u0430\u0437\u0435 \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 SMB, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u043a\u0440\u0438\u0442\u0438\u0447\u0435\u0441\u043a\u0430\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e \u0434\u043e\u0431\u0438\u0442\u044c\u0441\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u0441\u0432\u043e\u0435\u0433\u043e \u043a\u043e\u0434\u0430 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 \u044f\u0434\u0440\u0430. \u0410\u0442\u0430\u043a\u0430 \u043c\u043e\u0436\u0435\u0442 \u0431\u044b\u0442\u044c \u043f\u0440\u043e\u0432\u0435\u0434\u0435\u043d\u0430 \u0431\u0435\u0437 \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438, \u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u043e \u0447\u0442\u043e\u0431\u044b \u043d\u0430 \u0441\u0438\u0441\u0442\u0435\u043c\u0435 \u0431\u044b\u043b \u0430\u043a\u0442\u0438\u0432\u0438\u0440\u043e\u0432\u0430\u043d \u043c\u043e\u0434\u0443\u043b\u044c ksmbd. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u043d\u0430\u0447\u0438\u043d\u0430\u044f \u0441 \u044f\u0434\u0440\u0430 5.15, \u0432\u044b\u043f\u0443\u0449\u0435\u043d\u043d\u043e\u0433\u043e \u0432 \u043d\u043e\u044f\u0431\u0440\u0435 2021 \u0433\u043e\u0434\u0430, \u0438 \u0431\u0435\u0437 \u043b\u0438\u0448\u043d\u0435\u0439 […]<\/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-106241","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\udd47 Vulnerabilidade no m\u00f3dulo ksmbd do n\u00facleo Linux, permitindo a execu\u00e7\u00e3o remota de c\u00f3digo | ProHoster","description":"Uma vulnerabilidade cr\u00edtica foi identificada no m\u00f3dulo ksmbd, que inclui uma implementa\u00e7\u00e3o integrada no n\u00facleo Linux de um servidor de arquivos baseado no protocolo SMB, permitindo a execu\u00e7\u00e3o remota de c\u00f3digo com privil\u00e9gios de 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\u043a\u043e\u0434 | ProHoster","og:description":"\u0412 \u043c\u043e\u0434\u0443\u043b\u0435 ksmbd, \u0432\u043a\u043b\u044e\u0447\u0430\u044e\u0449\u0435\u043c \u0432\u0441\u0442\u0440\u043e\u0435\u043d\u043d\u0443\u044e \u0432 \u044f\u0434\u0440\u043e Linux \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u044e \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 \u043d\u0430 \u0431\u0430\u0437\u0435 \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 SMB, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u043a\u0440\u0438\u0442\u0438\u0447\u0435\u0441\u043a\u0430\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e \u0434\u043e\u0431\u0438\u0442\u044c\u0441\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u0441\u0432\u043e\u0435\u0433\u043e \u043a\u043e\u0434\u0430 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 \u044f\u0434\u0440\u0430.","og:url":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimost-v-module-ksmbd-yadra-linux-pozvolyayushhaya-udalyonno-vypolnit-svoj-kod","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":"2022-12-23T07:36:47+00:00","article:modified_time":"2022-12-23T07:36:47+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\/106241","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=106241"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/106241\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media?parent=106241"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/categories?post=106241"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/tags?post=106241"}],"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":"