{"id":41582,"date":"2020-02-12T16:19:30","date_gmt":"2020-02-12T13:19:30","guid":{"rendered":"https:\/\/prohoster.info\/blog\/blog_prohoster\/uyazvimost-v-systemd-potenczialno-pozvolyayushhaya-povysit-svoi-privilegii"},"modified":"2020-02-12T16:19:30","modified_gmt":"2020-02-12T13:19:30","slug":"uyazvimost-v-systemd-potenczialno-pozvolyayushhaya-povysit-svoi-privilegii","status":"publish","type":"post","link":"https:\/\/prohoster.info\/es\/blog\/uyazvimost-v-systemd-potenczialno-pozvolyayushhaya-povysit-svoi-privilegii","title":{"rendered":"Una vulnerabilidad en systemd, que potencialmente podr\u00eda permitir elevar privilegios","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

En el gestor de sistemas systemd se ha detectado<\/a><\/noindex> una vulnerabilidad (CVE-2020-1712<\/a><\/noindex>), que potencialmente permite ejecutar c\u00f3digo con privilegios elevados al enviar una solicitud especialmente formada a trav\u00e9s del bus DBus. El problema ha sido corregido en la versi\u00f3n de prueba systemd 245-rc1<\/a><\/noindex> (parches que resuelven el problema: 1<\/a><\/noindex>, 2<\/a><\/noindex>, 3<\/a><\/noindex>). La vulnerabilidad ha sido solucionada en las distribuciones Ubuntu<\/a><\/noindex>, Fedora<\/a><\/noindex>, RHEL<\/a><\/noindex> (se manifiesta en RHEL 8, pero no afecta a RHEL 7), CentOS<\/a><\/noindex>, SUSE\/openSUSE<\/a><\/noindex> y ROSA<\/a><\/noindex>, pero al momento de redactar esta noticia permanece sin soluci\u00f3n en Debian<\/a><\/noindex> y Arch Linux<\/a><\/noindex>. <\/p>\n

La vulnerabilidad es causada por acceder a un \u00e1rea de memoria ya liberada (use-after-free), que ocurre durante la ejecuci\u00f3n asincr\u00f3nica de solicitudes a Polkit al procesar mensajes de DBus. Algunos interfaces de DBus utilizan un cach\u00e9 para almacenar objetos por un corto tiempo y eliminan los elementos del cach\u00e9 tan pronto como el bus de DBus se libera para manejar otras solicitudes. Si el manejador del m\u00e9todo DBus utiliza bus_verify_polkit_async(), puede ser necesario esperar a que la acci\u00f3n en Polkit se complete. Una vez que Polkit est\u00e1 listo, se llama nuevamente al manejador y accede a datos que previamente se hab\u00edan asignado en memoria. Si la solicitud a Polkit tarda demasiado, los elementos en el cach\u00e9 pueden eliminarse antes de que el manejador del m\u00e9todo DBus sea llamado por segunda vez. <\/p>\n

Entre los servicios que permiten explotar la vulnerabilidad se encuentra systemd-machined, que proporciona la API de DBus org.freedesktop.machine1.Image.Clone, lo que conduce a la conservaci\u00f3n temporal de datos en el cach\u00e9 y a la interacci\u00f3n asincr\u00f3nica con Polkit. La interfaz
\norg.freedesktop.machine1.Image.Clone est\u00e1 disponible para todos los usuarios no privilegiados del sistema, que pueden iniciar un fallo en los servicios de systemd o potencialmente lograr ejecutar c\u00f3digo con privilegios de root (el prototipo del exploit a\u00fan no ha sido demostrado). El c\u00f3digo que permite explotar la vulnerabilidad fue se ha agregado<\/a><\/noindex> en systemd-machined en 2015 en la versi\u00f3n systemd 220<\/a><\/noindex> (en RHEL 7.x se utiliza systemd 219). <\/p>\n

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

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

\u0412 \u0441\u0438\u0441\u0442\u0435\u043c\u043d\u043e\u043c \u043c\u0435\u043d\u0435\u0434\u0436\u0435\u0440\u0435 systemd \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (CVE-2020-1712), \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043f\u043e\u0442\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u0435\u0442 \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\u043e\u0432\u044b\u0448\u0435\u043d\u043d\u044b\u043c\u0438 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u044f\u043c\u0438 \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 \u0437\u0430\u043f\u0440\u043e\u0441\u0430 \u043f\u043e \u0448\u0438\u043d\u0435 DBus. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u0438\u0441\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0430 \u0432 \u0442\u0435\u0441\u0442\u043e\u0432\u043e\u043c \u0432\u044b\u043f\u0443\u0441\u043a\u0435 systemd 245-rc1 (\u0440\u0435\u0448\u0430\u044e\u0449\u0438\u0435 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0443 \u043f\u0430\u0442\u0447\u0438: 1, 2, 3). \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430 \u0432 \u0434\u0438\u0441\u0442\u0440\u0438\u0431\u0443\u0442\u0438\u0432\u0430\u0445 Ubuntu, Fedora, RHEL (\u043f\u0440\u043e\u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u0432 RHEL 8, \u043d\u043e \u043d\u0435 \u0437\u0430\u0442\u0440\u0430\u0433\u0438\u0432\u0430\u0435\u0442 RHEL 7), CentOS, […]<\/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":[],"tags":[],"class_list":["post-41582","post","type-post","status-publish","format-standard","hentry"],"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\udd47Vulnerabilidad en systemd que potencialmente permite elevar privilegios | ProHoster","description":"Se ha identificado una vulnerabilidad en el gestor de sistemas systemd (","canonical_url":"https:\/\/prohoster.info\/es\/blog\/uyazvimost-v-systemd-potenczialno-pozvolyayushhaya-povysit-svoi-privilegii","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"es_ES","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 systemd, \u043f\u043e\u0442\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043f\u043e\u0432\u044b\u0441\u0438\u0442\u044c \u0441\u0432\u043e\u0438 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0438 | ProHoster","og:description":"\u0412 \u0441\u0438\u0441\u0442\u0435\u043c\u043d\u043e\u043c \u043c\u0435\u043d\u0435\u0434\u0436\u0435\u0440\u0435 systemd \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (","og:url":"https:\/\/prohoster.info\/es\/blog\/uyazvimost-v-systemd-potenczialno-pozvolyayushhaya-povysit-svoi-privilegii","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":"2020-02-12T13:19:30+00:00","article:modified_time":"2020-02-12T13:19:30+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"41582","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":"2021-03-01 00:14:28","updated":"2022-09-30 17:11:33","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/posts\/41582","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/comments?post=41582"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/posts\/41582\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/media?parent=41582"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/categories?post=41582"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/es\/wp-json\/wp\/v2\/tags?post=41582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}