{"id":105785,"date":"2022-12-02T15:36:49","date_gmt":"2022-12-02T13:36:49","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/root-uyazvimost-v-instrumentarii-upravleniya-paketami-snap"},"modified":"2022-12-02T15:36:49","modified_gmt":"2022-12-02T13:36:49","slug":"root-uyazvimost-v-instrumentarii-upravleniya-paketami-snap","status":"publish","type":"post","link":"https:\/\/prohoster.info\/hr\/blog\/news\/root-uyazvimost-v-instrumentarii-upravleniya-paketami-snap","title":{"rendered":"Root ranjivost u alatu za upravljanje paketima Snap","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Tvrtka Qualys otkrila je tre\u0107u opasnu ranjivost (CVE-2022-3328) u alatki snap-confine, koja se isporu\u010duje s SUID root oznakom i poziva proces snapd za stvaranje izvr\u0161nog okru\u017eenja za aplikacije distribuirane u samostalnim paketima u snap formatu. Ova ranjivost omogu\u0107uje lokalnom nepovla\u0161tenom korisniku da izvr\u0161i kod s root pravima u zadanoj konfiguraciji Ubuntu-a. Problem je ispravljen u izdanju snapd 2.57.6. A\u017euriranja paketa objavljena su za sve podr\u017eane grane Ubuntu-a. <\/p>\n

Zanimljivo je da je spomenuta ranjivost nastala tijekom ispravljanja sli\u010dne ranjivosti iz velja\u010de u snap-confine. Istra\u017eiva\u010dima je uspjelo pripremiti radni exploit koji omogu\u0107uje root pristup na Ubuntu Server 22.04, gdje su osim ranjivosti u snap-confine uklju\u010dene i dvije ranjivosti u procesu multipathd (CVE-2022-41974, CVE-2022-41973) vezane uz zaobila\u017eenje provjere ovla\u0161tenja prilikom preno\u0161enja privilegiranih naredbi i nesigurnog rada s simboli\u010dkim vezama. <\/p>\n

Ranjivost u snap-confine uzrokovana je stanjem utrke u funkciji must_mkdir_and_open_with_perms(), koja je dodana kao za\u0161tita od supstitucije direktorija \/tmp\/snap.$SNAP_NAME s simboli\u010dkom vezom nakon provjere vlasnika, ali prije poziva na sustavni poziv mount za bind-montiranje direktorija za snap paket. Dodana za\u0161tita svodila se na preimenovanje direktorija \/tmp\/snap.$SNAP_NAME u drugi direktorij u \/tmp s nasumi\u010dnim imenom, ako on postoji i ne pripada korisniku root. <\/p>\n

Tijekom izvo\u0111enja operacije preimenovanja direktorija \/tmp\/snap.$SNAP_NAME, istra\u017eiva\u010di su iskoristili to \u0161to snap-confine tako\u0111er stvara direktorij \/tmp\/snap.rootfs_XXXXXX za korijen sadr\u017eaja snap paketa. Dio 'XXXXXX' u imenu se nasumi\u010dno odabire pomo\u0107u mkdtemp(), ali paket s imenom 'rootfs_XXXXXX' mo\u017ee pro\u0107i provjeru u funkciji sc_instance_name_validate (tj. ideja je da ime $SNAP_NAME postane 'rootfs_XXXXXX' i tada \u0107e operacija preimenovanja rezultirati prepisivanjem direktorija \/tmp\/snap.rootfs_XXXXXX s korijenom snap). <\/p>\n

Kako bi se omogu\u0107ila istovremena upotreba \/tmp\/snap.rootfs_XXXXXX i preimenovanje \/tmp\/snap.$SNAP_NAME, pokrenuta su dva primjerka snap-confine. Kada je prvi primjerak stvorio \/tmp\/snap.rootfs_XXXXXX, proces se blokirao, a drugi primjerak s imenom paketa rootfs_XXXXXX se pokrenuo, \u0161to je dovelo do toga da je privremeni direktorij \/tmp\/snap.$SNAP_NAME drugog primjerka postao korijenski direktorij \/tmp\/snap.rootfs_XXXXXX prvog. Odmah nakon izvr\u0161enja preimenovanja, drugi primjerak je neo\u010dekivano zavr\u0161io, a \/tmp\/snap.rootfs_XXXXXX je zamijenjen manipulacijom sa stanjem utrke, sli\u010dno iskori\u0161tavanju ranjivosti iz velja\u010de. Nakon zamjene, blokada izvr\u0161enja prvog primjerka je uklonjena, a napada\u010di su dobili punu kontrolu nad korijenskim direktorijem snap. <\/p>\n

U zadnjem koraku je stvorena simboli\u010dka poveznica \/tmp\/snap.rootfs_XXXXXX\/tmp, koja se koristila funkcijom sc_bootstrap_mount_namespace() za bind-montiranje dostupnog za pisanje stvarnog direktorija \/tmp u bilo koji direktorij FS, budu\u0107i da poziv mount() slijedi simboli\u010dkim vezama prije montiranja. Takvo montiranje je blokirano ograni\u010denjima AppArmor, ali su za obila\u017eenje ove blokade u exploit uklju\u010dene dvije pomo\u0107ne ranjivosti u multipathd.
\n
Izvor: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u041a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Qualys \u0432\u044b\u044f\u0432\u0438\u043b\u0430 \u0442\u0440\u0435\u0442\u044c\u044e \u0432 \u044d\u0442\u043e\u043c\u0443 \u0433\u043e\u0434\u0443 \u043e\u043f\u0430\u0441\u043d\u0443\u044e \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (CVE-2022-3328) \u0432 \u0443\u0442\u0438\u043b\u0438\u0442\u0435 snap-confine, \u043f\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u043c\u043e\u0439 \u0441 \u0444\u043b\u0430\u0433\u043e\u043c SUID root \u0438 \u0432\u044b\u0437\u044b\u0432\u0430\u0435\u043c\u043e\u0439 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u043c snapd \u0434\u043b\u044f \u0444\u043e\u0440\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u0438\u0441\u043f\u043e\u043b\u043d\u044f\u0435\u043c\u043e\u0433\u043e \u043e\u043a\u0440\u0443\u0436\u0435\u043d\u0438\u044f \u0434\u043b\u044f \u043f\u0440\u0438\u043b\u043e\u0436\u0435\u043d\u0438\u0439, \u0440\u0430\u0441\u043f\u0440\u043e\u0441\u0442\u0440\u0430\u043d\u044f\u0435\u043c\u044b\u0445 \u0432 \u0441\u0430\u043c\u043e\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u044b\u0445 \u043f\u0430\u043a\u0435\u0442\u0430\u0445 \u0432 \u0444\u043e\u0440\u043c\u0430\u0442\u0435 snap. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u0435\u0442 \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 \u0434\u043e\u0431\u0438\u0442\u044c\u0441\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u043a\u043e\u0434\u0430 \u0441 \u043f\u0440\u0430\u0432\u0430\u043c\u0438 root \u0432 \u043a\u043e\u043d\u0444\u0438\u0433\u0443\u0440\u0430\u0446\u0438\u0438 Ubuntu \u043f\u043e \u0443\u043c\u043e\u043b\u0447\u0430\u043d\u0438\u044e. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430 \u0432 \u0432\u044b\u043f\u0443\u0441\u043a\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-105785","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\udd47Root-ranjivost u paketu Snap Management Tool | ProHoster","description":"Tvrtka Qualys je otkrila tre\u0107u opasnu ranjivost (CVE-2022-3328) ove godine u alatu snap-confine, isporu\u010denom s root SUID zastavicom i pozvanom od strane procesa snapd kako bi formirala izvr\u0161no okru\u017eenje za.","canonical_url":"https:\/\/prohoster.info\/hr\/blog\/news\/root-uyazvimost-v-instrumentarii-upravleniya-paketami-snap","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"hr_HR","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\udd47Root-\u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432 \u0438\u043d\u0441\u0442\u0440\u0443\u043c\u0435\u043d\u0442\u0430\u0440\u0438\u0438 \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u043f\u0430\u043a\u0435\u0442\u0430\u043c\u0438 Snap | ProHoster","og:description":"\u041a\u043e\u043c\u043f\u0430\u043d\u0438\u044f Qualys \u0432\u044b\u044f\u0432\u0438\u043b\u0430 \u0442\u0440\u0435\u0442\u044c\u044e \u0432 \u044d\u0442\u043e\u043c\u0443 \u0433\u043e\u0434\u0443 \u043e\u043f\u0430\u0441\u043d\u0443\u044e \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c (CVE-2022-3328) \u0432 \u0443\u0442\u0438\u043b\u0438\u0442\u0435 snap-confine, \u043f\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u043c\u043e\u0439 \u0441 \u0444\u043b\u0430\u0433\u043e\u043c SUID root \u0438 \u0432\u044b\u0437\u044b\u0432\u0430\u0435\u043c\u043e\u0439 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u043c snapd \u0434\u043b\u044f \u0444\u043e\u0440\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u0438\u0441\u043f\u043e\u043b\u043d\u044f\u0435\u043c\u043e\u0433\u043e \u043e\u043a\u0440\u0443\u0436\u0435\u043d\u0438\u044f \u0434\u043b\u044f.","og:url":"https:\/\/prohoster.info\/hr\/blog\/news\/root-uyazvimost-v-instrumentarii-upravleniya-paketami-snap","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":"2022-12-02T13:36:49+00:00","article:modified_time":"2022-12-02T13:36:49+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\/hr\/wp-json\/wp\/v2\/posts\/105785","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/comments?post=105785"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/posts\/105785\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/media?parent=105785"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/categories?post=105785"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/tags?post=105785"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}