{"id":93183,"date":"2020-09-04T07:42:02","date_gmt":"2020-09-04T05:42:02","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/uyazvimost-v-realizaczii-soketov-af_packet-yadra-linux"},"modified":"2020-09-04T07:42:02","modified_gmt":"2020-09-04T05:42:02","slug":"uyazvimost-v-realizaczii-soketov-af_packet-yadra-linux","status":"publish","type":"post","link":"https:\/\/prohoster.info\/sv\/blog\/news\/uyazvimost-v-realizaczii-soketov-af_packet-yadra-linux","title":{"rendered":"S\u00e5rbarhet i implementeringen av AF_PACKET-sockets i Linux-k\u00e4rnan","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Tre \u00e5r efter att ett flertal s\u00e5rbarheter uppt\u00e4cktes (1<\/a><\/noindex>, 2<\/a><\/noindex>, 3<\/a><\/noindex>, 4<\/a><\/noindex>, 5<\/a><\/noindex>) i AF_PACKET-subsystemet i Linux-k\u00e4rnan uppt\u00e4cktes<\/a><\/noindex> har \u00e4nnu ett problem uppt\u00e4ckts (CVE-2020-14386<\/a><\/noindex>), som g\u00f6r det m\u00f6jligt f\u00f6r en lokal, icke-beh\u00f6rig anv\u00e4ndare att k\u00f6ra kod med root-beh\u00f6righet eller ta sig ut ur isolerade containrar, f\u00f6rutsatt att de har root-\u00e5tkomst.<\/p>\n

F\u00f6r att skapa en AF_PACKET-socket och utnyttja s\u00e5rbarheten kr\u00e4vs beh\u00f6righeten CAP_NET_RAW. Dock kan den n\u00e4mnda beh\u00f6righeten erh\u00e5llas av en icke-beh\u00f6rig anv\u00e4ndare i containrar som skapats i system med aktiverad st\u00f6d f\u00f6r anv\u00e4ndarnamnrymder (user namespaces). Till exempel, \u00e4r anv\u00e4ndarnamnrymder som standard aktiverade i Ubuntu och Fedora, men inte aktiverade i Debian och RHEL. I Android har processen mediaserver r\u00e4tt att skapa AF_PACKET-sockets, vilket kan utnyttja s\u00e5rbarheten.<\/p>\n

S\u00e5rbarheten finns i funktionen tpacket_rcv och orsakas av ett fel i ber\u00e4kningen av variabeln netoff. En angripare kan skapa f\u00f6rh\u00e5llanden under vilka ett v\u00e4rde mindre \u00e4n variabeln maclen skrivs till netoff, vilket kommer att leda till en \u00f6verfl\u00f6de vid ber\u00e4kningen av \"macoff = netoff - maclen\" och en felaktig efterf\u00f6ljande inst\u00e4llning av pekaren till buffern f\u00f6r de inkommande data. Som en f\u00f6ljd kan angripare initiera en skrivning p\u00e5 mellan 1 och 10 byte i omr\u00e5det utanf\u00f6r den tilldelade bufferten. Det noteras att en exploit \u00e4r under utveckling som m\u00f6jligg\u00f6r att f\u00e5 root-r\u00e4ttigheter i systemet. <\/p>\n

Problemet har funnits i k\u00e4rnan sedan juli 2008, det vill s\u00e4ga det f\u00f6rekommer i alla aktuella k\u00e4rnor. En l\u00f6sning \u00e4r f\u00f6r n\u00e4rvarande tillg\u00e4nglig i form av en patch<\/a><\/noindex>. F\u00f6r att sp\u00e5ra uppdateringar av paketer i distributionerna kan man bes\u00f6ka f\u00f6ljande sidor: Ubuntu<\/a><\/noindex>, Fedora<\/a><\/noindex>, SUSE<\/a><\/noindex>, Debian<\/a><\/noindex>, RHEL<\/a><\/noindex>, Arch<\/a><\/noindex>.<\/p>\n

<\/a><\/noindex><\/p>\n

K\u00e4lla: opennet.ru<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0421\u043f\u0443\u0441\u0442\u044f \u0442\u0440\u0438 \u0433\u043e\u0434\u0430 \u0441 \u043c\u043e\u043c\u0435\u043d\u0442\u0430 \u0432\u043e\u043b\u043d\u044b \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439 (1, 2, 3, 4, 5) \u0432 \u043f\u043e\u0434\u0441\u0438\u0441\u0442\u0435\u043c\u0435 AF_PACKET \u044f\u0434\u0440\u0430 Linux \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0435\u0449\u0451 \u043e\u0434\u043d\u0430 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 (CVE-2020-14386), \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u043e\u043c\u0443 \u043d\u0435\u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u043e\u043c\u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044e \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root \u0438\u043b\u0438 \u0432\u044b\u0439\u0442\u0438 \u0438\u0437 \u0438\u0437\u043e\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u044b\u0445 \u043a\u043e\u043d\u0442\u0435\u0439\u043d\u0435\u0440\u043e\u0432, \u043f\u0440\u0438 \u043d\u0430\u043b\u0438\u0447\u0438\u0438 \u0432 \u043d\u0438\u0445 root-\u0434\u043e\u0441\u0442\u0443\u043f\u0430. \u0414\u043b\u044f \u0441\u043e\u0437\u0434\u0430\u043d\u0438\u044f \u0441\u043e\u043a\u0435\u0442\u0430 AF_PACKET \u0438 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u0442\u0440\u0435\u0431\u0443\u0435\u0442\u0441\u044f \u043d\u0430\u043b\u0438\u0447\u0438\u0435 \u043f\u043e\u043b\u043d\u043e\u043c\u043e\u0447\u0438\u0439 CAP_NET_RAW. \u0422\u0435\u043c \u043d\u0435 \u043c\u0435\u043d\u0435\u0435, […]<\/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-93183","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\udd47S\u00e5rbarhet i implementeringen av AF_PACKET-sockets i Linux-k\u00e4rnan | ProHoster","description":"Tre \u00e5r efter att ett flertal s\u00e5rbarheter uppt\u00e4cktes (1,","canonical_url":"https:\/\/prohoster.info\/sv\/blog\/news\/uyazvimost-v-realizaczii-soketov-af_packet-yadra-linux","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"sv_SE","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\u044c \u0432 \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u0441\u043e\u043a\u0435\u0442\u043e\u0432 AF_PACKET \u044f\u0434\u0440\u0430 Linux | ProHoster","og:description":"\u0421\u043f\u0443\u0441\u0442\u044f \u0442\u0440\u0438 \u0433\u043e\u0434\u0430 \u0441 \u043c\u043e\u043c\u0435\u043d\u0442\u0430 \u0432\u043e\u043b\u043d\u044b \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439 (1,","og:url":"https:\/\/prohoster.info\/sv\/blog\/news\/uyazvimost-v-realizaczii-soketov-af_packet-yadra-linux","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":"2020-09-04T05:42:02+00:00","article:modified_time":"2020-09-04T05:42:02+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"93183","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":"2021-02-28 11:52:32","updated":"2022-09-28 05:10:35","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/posts\/93183","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/comments?post=93183"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/posts\/93183\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/media?parent=93183"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/categories?post=93183"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/sv\/wp-json\/wp\/v2\/tags?post=93183"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}