{"id":170683,"date":"2026-05-15T00:24:28","date_gmt":"2026-05-14T22:24:28","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root"},"modified":"2026-05-15T00:24:28","modified_gmt":"2026-05-14T22:24:28","slug":"uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root","status":"publish","type":"post","link":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root","title":{"rendered":"Vulnerabilidades no dnsmasq que permitem envenenamento do cache DNS e execu\u00e7\u00e3o de c\u00f3digo com privil\u00e9gios de root","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p>No pacote Dnsmasq, que combina um resolutor DNS em cache, servidor DHCP, servi\u00e7o para an\u00fancios de rotas IPv6 e sistema de inicializa\u00e7\u00e3o pela rede, foram identificadas 6 vulnerabilidades que permitem a execu\u00e7\u00e3o de c\u00f3digo com privil\u00e9gios de root, redirecionar um dom\u00ednio para outro IP, acessar o conte\u00fado da mem\u00f3ria de um processo e causar a falha do servi\u00e7o. Os problemas foram corrigidos na vers\u00e3o dnsmasq 2.92rel2. As corre\u00e7\u00f5es tamb\u00e9m est\u00e3o dispon\u00edveis na forma de patches.             <\/p>\n<p>Problemas identificados:  <\/p>\n<ul>\n<li class=\"l\"> CVE-2026-4892 \u2014 um estouro de buffer na implementa\u00e7\u00e3o do DHCPv6, permitindo que um atacante com acesso \u00e0 rede local execute c\u00f3digo com privil\u00e9gios de root ao enviar um pacote DHCPv6 especialmente formatado. O estouro \u00e9 causado pelo fato de que, ao gravar o CLID do DHCPv6 no buffer, n\u00e3o foi considerado que os dados no pacote est\u00e3o armazenados em representa\u00e7\u00e3o hexadecimal, na qual s\u00e3o utilizados tr\u00eas bytes '%xx' para cada byte real do CLID (por exemplo, salvar um CLID de 1000 bytes resultar\u00e1 na grava\u00e7\u00e3o de 3000 bytes).\n<li class=\"l\"> CVE-2026-2291 \u2014 estouro de buffer na fun\u00e7\u00e3o extract_name(), permitindo que um atacante insira registros falsos no cache DNS e consiga redirecionamento. <a class=\"wpil_keyword_link\" href=\"https:\/\/prohoster.info\/pt\/domain\/\" title=\"de dom\u00ednio\" data-wpil-keyword-link=\"linked\">de dom\u00ednio<\/a> para outro endere\u00e7o IP. O estouro ocorreu devido \u00e0 aloca\u00e7\u00e3o do buffer sem considerar a escapagem de alguns caracteres na representa\u00e7\u00e3o interna do nome de dom\u00ednio no dnsmasq.\n<li class=\"l\"> CVE-2026-4893 \u2014 vazamento de informa\u00e7\u00f5es, permitindo contornar a verifica\u00e7\u00e3o ao enviar um pacote DNS especialmente formatado com informa\u00e7\u00f5es sobre a sub-rede do cliente (RFC 7871). A vulnerabilidade pode ser utilizada para alterar o roteamento da resposta DNS e redirecionar usu\u00e1rios para o dom\u00ednio do invasor. A vulnerabilidade \u00e9 causada pelo fato de que o comprimento do registro OPT foi passado para a fun\u00e7\u00e3o check_source() em vez do comprimento do pacote, resultando sempre em um resultado de verifica\u00e7\u00e3o bem-sucedido.\n<li class=\"l\"> CVE-2026-4891 \u2014 leitura fora dos limites do buffer ao validar DNSSEC, resultando em vazamento de dados da mem\u00f3ria do processo na resposta ao tratar um pedido DNS especialmente formatado.\n<li class=\"l\"> CVE-2026-4890 \u2014 looping ao validar DNSSEC, permitindo causar uma nega\u00e7\u00e3o de servi\u00e7o ao enviar um pacote DNS especialmente formatado.\n<li class=\"l\"> CVE-2026-5172 \u2014 leitura fora do buffer na fun\u00e7\u00e3o extract_addresses(), resultando em falha ao processar respostas DNS especialmente formatadas.  <\/ul>\n<p>O status da corre\u00e7\u00e3o de vulnerabilidades em distribui\u00e7\u00f5es pode ser avaliado nas seguintes p\u00e1ginas (se a p\u00e1gina n\u00e3o estiver dispon\u00edvel, significa que os desenvolvedores da distribui\u00e7\u00e3o ainda n\u00e3o come\u00e7aram a considerar o problema): Debian, Ubuntu, SUSE, RHEL, Gentoo, Arch, Fedora, OpenWRT, FreeBSD. O projeto Dnsmasq est\u00e1 envolvido na plataforma Android e em distribui\u00e7\u00f5es especializadas, como OpenWrt e DD-WRT, assim como em firmwares de muitos fabricantes de roteadores sem fio. Em distribui\u00e7\u00f5es comuns, o Dnsmasq pode ser instalado ao usar o libvirt para garantir o funcionamento do servi\u00e7o DNS em <a class=\"wpil_keyword_link\" href=\"https:\/\/prohoster.info\/pt\/vps\/abuzoustojchivye-vps\/\" title=\"m\u00e1quinas virtuais\" data-wpil-keyword-link=\"linked\">m\u00e1quinas virtuais<\/a> ou pode ser ativado no configurador NetworkManager.<br \/>\n<br \/>Fonte: <a rel=\"nofollow\" href=\"https:\/\/www.opennet.ru\/opennews\/art.shtml?num=65431\">opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u0412 \u043f\u0430\u043a\u0435\u0442\u0435 Dnsmasq, \u043e\u0431\u044a\u0435\u0434\u0438\u043d\u044f\u044e\u0449\u0435\u043c \u043a\u044d\u0448\u0438\u0440\u0443\u044e\u0449\u0438\u0439 DNS-\u0440\u0435\u0437\u043e\u043b\u0432\u0435\u0440, \u0441\u0435\u0440\u0432\u0435\u0440 DHCP, \u0441\u0435\u0440\u0432\u0438\u0441 \u0434\u043b\u044f \u0430\u043d\u043e\u043d\u0441\u043e\u0432 \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u043e\u0432 IPv6 \u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u0443 \u0437\u0430\u0433\u0440\u0443\u0437\u043a\u0438 \u043f\u043e \u0441\u0435\u0442\u0438, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u043e 6 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root, \u043f\u0435\u0440\u0435\u043d\u0430\u043f\u0440\u0430\u0432\u0438\u0442\u044c \u0434\u043e\u043c\u0435\u043d \u043d\u0430 \u0434\u0440\u0443\u0433\u043e\u0439 IP, \u043e\u043f\u0440\u0435\u0434\u0435\u043b\u0438\u0442\u044c \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0435 \u043f\u0430\u043c\u044f\u0442\u0438 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u0430 \u0438 \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u0430\u0432\u0430\u0440\u0438\u0439\u043d\u043e\u0435 \u0437\u0430\u0432\u0435\u0440\u0448\u0435\u043d\u0438\u0435 \u0441\u0435\u0440\u0432\u0438\u0441\u0430. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u044b \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u044b \u0432 \u0432\u044b\u043f\u0443\u0441\u043a\u0435 dnsmasq 2.92rel2. \u0418\u0441\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u0442\u0430\u043a\u0436\u0435 \u0434\u043e\u0441\u0442\u0443\u043f\u043d\u044b \u0432 \u0444\u043e\u0440\u043c\u0435 \u043f\u0430\u0442\u0447\u0435\u0439. \u0412\u044b\u044f\u0432\u043b\u0435\u043d\u043d\u044b\u0435 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u044b: [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-170683","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"\u0412 \u043f\u0430\u043a\u0435\u0442\u0435 Dnsmasq, \u043e\u0431\u044a\u0435\u0434\u0438\u043d\u044f\u044e\u0449\u0435\u043c \u043a\u044d\u0448\u0438\u0440\u0443\u044e\u0449\u0438\u0439 DNS-\u0440\u0435\u0437\u043e\u043b\u0432\u0435\u0440, \u0441\u0435\u0440\u0432\u0435\u0440 DHCP, \u0441\u0435\u0440\u0432\u0438\u0441 \u0434\u043b\u044f \u0430\u043d\u043e\u043d\u0441\u043e\u0432 \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u043e\u0432 IPv6 \u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u0443 \u0437\u0430\u0433\u0440\u0443\u0437\u043a\u0438 \u043f\u043e \u0441\u0435\u0442\u0438, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u043e 6 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root, \u043f\u0435\u0440\u0435\u043d\u0430\u043f\u0440\u0430\u0432\u0438\u0442\u044c \u0434\u043e\u043c\u0435\u043d.\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"Erik Peterson\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.3\" \/>\n\t\t<meta property=\"og:locale\" content=\"pt_PT\" \/>\n\t\t<meta property=\"og:site_name\" content=\"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\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"\ud83e\udd47\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u0432 dnsmasq, \u0434\u043e\u043f\u0443\u0441\u043a\u0430\u044e\u0449\u0438\u0435 \u043e\u0442\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u0435 DNS-\u043a\u044d\u0448\u0430 \u0438 \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u0435 \u043a\u043e\u0434\u0430 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root | ProHoster\" \/>\n\t\t<meta property=\"og:description\" content=\"\u0412 \u043f\u0430\u043a\u0435\u0442\u0435 Dnsmasq, \u043e\u0431\u044a\u0435\u0434\u0438\u043d\u044f\u044e\u0449\u0435\u043c \u043a\u044d\u0448\u0438\u0440\u0443\u044e\u0449\u0438\u0439 DNS-\u0440\u0435\u0437\u043e\u043b\u0432\u0435\u0440, \u0441\u0435\u0440\u0432\u0435\u0440 DHCP, \u0441\u0435\u0440\u0432\u0438\u0441 \u0434\u043b\u044f \u0430\u043d\u043e\u043d\u0441\u043e\u0432 \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u043e\u0432 IPv6 \u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u0443 \u0437\u0430\u0433\u0440\u0443\u0437\u043a\u0438 \u043f\u043e \u0441\u0435\u0442\u0438, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u043e 6 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root, \u043f\u0435\u0440\u0435\u043d\u0430\u043f\u0440\u0430\u0432\u0438\u0442\u044c \u0434\u043e\u043c\u0435\u043d.\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:width\" content=\"350\" \/>\n\t\t<meta property=\"og:image:height\" content=\"350\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2026-05-14T22:24:28+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2026-05-14T22:24:28+00:00\" \/>\n\t\t<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"\ud83e\udd47Vulnerabilidades no dnsmasq que permitem envenenamento de cache DNS e execu\u00e7\u00e3o de c\u00f3digo com privil\u00e9gios de root | ProHoster","description":"O pacote Dnsmasq, que combina um resolvedor DNS em cache, servidor DHCP, servi\u00e7o para an\u00fancios de rotas IPv6 e sistema de inicializa\u00e7\u00e3o pela rede, identificou 6 vulnerabilidades que permitem a execu\u00e7\u00e3o de c\u00f3digo com privil\u00e9gios de root, redirecionamento de dom\u00ednio.","canonical_url":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root","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 dnsmasq, \u0434\u043e\u043f\u0443\u0441\u043a\u0430\u044e\u0449\u0438\u0435 \u043e\u0442\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u0435 DNS-\u043a\u044d\u0448\u0430 \u0438 \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u0435 \u043a\u043e\u0434\u0430 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root | ProHoster","og:description":"\u0412 \u043f\u0430\u043a\u0435\u0442\u0435 Dnsmasq, \u043e\u0431\u044a\u0435\u0434\u0438\u043d\u044f\u044e\u0449\u0435\u043c \u043a\u044d\u0448\u0438\u0440\u0443\u044e\u0449\u0438\u0439 DNS-\u0440\u0435\u0437\u043e\u043b\u0432\u0435\u0440, \u0441\u0435\u0440\u0432\u0435\u0440 DHCP, \u0441\u0435\u0440\u0432\u0438\u0441 \u0434\u043b\u044f \u0430\u043d\u043e\u043d\u0441\u043e\u0432 \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u043e\u0432 IPv6 \u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u0443 \u0437\u0430\u0433\u0440\u0443\u0437\u043a\u0438 \u043f\u043e \u0441\u0435\u0442\u0438, \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u043e 6 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0445 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root, \u043f\u0435\u0440\u0435\u043d\u0430\u043f\u0440\u0430\u0432\u0438\u0442\u044c \u0434\u043e\u043c\u0435\u043d.","og:url":"https:\/\/prohoster.info\/pt\/blog\/news\/uyazvimosti-v-dnsmasq-dopuskayushhie-otravlenie-dns-kesha-i-vypolnenie-koda-s-pravami-root","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":"2026-05-14T22:24:28+00:00","article:modified_time":"2026-05-14T22:24:28+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\/170683","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\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/comments?post=170683"}],"version-history":[{"count":1,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/170683\/revisions"}],"predecessor-version":[{"id":170707,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/170683\/revisions\/170707"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media?parent=170683"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/categories?post=170683"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/tags?post=170683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}