{"id":181668,"date":"2026-05-23T00:25:11","date_gmt":"2026-05-22T22:25:11","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/gro-frag-sedmaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux"},"modified":"2026-05-23T00:25:11","modified_gmt":"2026-05-22T22:25:11","slug":"gro-frag-sedmaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/news\/gro-frag-sedmaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","title":{"rendered":"GRO Frag \u2014 sedm\u00e1 zranitelnost t\u0159\u00eddy Copy Fail, poskytuj\u00edc\u00ed pr\u00e1va root v Linuxu","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Ve ve\u0159ejn\u00e9m prostoru byla zve\u0159ejn\u011bna exploita pro sedmou zranitelnost (1, 2-3, 4, 5, 6) v j\u00e1d\u0159e Linux, kter\u00e1 umo\u017e\u0148uje neprivilegovan\u00e9mu lok\u00e1ln\u00edmu u\u017eivateli z\u00edskat pr\u00e1va roota p\u0159eps\u00e1n\u00edm dat v str\u00e1nkov\u00e9m cache. CVE identifik\u00e1tor zat\u00edm nebyl p\u0159i\u0159azen, krom\u011b k\u00f3du exploitu zat\u00edm nejsou k dispozici \u017e\u00e1dn\u00e9 dal\u0161\u00ed informace o probl\u00e9mu. Oprava je dostupn\u00e1 pouze jako patch, kter\u00fd byl zve\u0159ejn\u011bn 20. kv\u011btna a 21. kv\u011btna byl p\u0159ijat do hlavn\u00ed v\u011btve j\u00e1dra Linux (opravy j\u00e1dra ale zat\u00edm nejsou k dispozici). <\/p>\n

Zranitelnost se vyskytuje v implementaci technologie GRO (Generic Receive Offload), kter\u00e1 se pou\u017e\u00edv\u00e1 k urychlen\u00ed zpracov\u00e1n\u00ed segmentovan\u00fdch paket\u016f. Zranitelnost je zp\u016fsobena chybou v implementaci mechanismu zerocopy v funkci skb_gro_receive(), kter\u00e1 prov\u00e1d\u00ed p\u0159\u00edmou zm\u011bnu dat ve str\u00e1nkov\u00e9m cache, aby se vylou\u010dilo zbyte\u010dn\u00e9 buferov\u00e1n\u00ed. P\u0159i nastaven\u00e9 vlajce SKBFL_MANAGED_FRAG_REFS do\u0161lo k opomenut\u00ed ulo\u017een\u00ed odkazu na uvoln\u011bn\u00e9 str\u00e1nky pam\u011bti do pole shinfo->frags, a toto pole bylo n\u00e1sledn\u011b p\u0159ipojeno k jin\u00e9mu skb bez zm\u011bny \u010d\u00edta\u010de odkaz\u016f, co\u017e vedlo k p\u0159\u00edstupu k pam\u011bti po jej\u00edm uvoln\u011bn\u00ed (use-after-free). Probl\u00e9m se poda\u0159ilo zneu\u017e\u00edt k p\u0159eps\u00e1n\u00ed dat ve str\u00e1nkov\u00e9m cache d\u00edky manipulaci s ukazatelem na buffer io_uring. <\/p>\n

\u00datok je mo\u017en\u00fd na syst\u00e9mech s aktivovanou podsyst\u00e9mem io_uring (io_uring_disabled=0). Pro fungov\u00e1n\u00ed exploit\u016f mus\u00ed b\u00fdt v syst\u00e9mu dostupn\u00fd ke \u010dten\u00ed spustiteln\u00fd soubor s flagem SUID-root. Mechanismus exploitu spo\u010d\u00edv\u00e1 v tom, \u017ee \u00fato\u010dn\u00edk zajist\u00ed ulo\u017een\u00ed datab\u00e1ze u\u017eivatel\u016f do str\u00e1nkov\u00e9ho cache, pot\u00e9 do cache vlo\u017e\u00ed \u0159et\u011bzec «hax::0:0::\/root:\/bin\/sh». N\u00e1sledn\u011b je spu\u0161t\u011bn p\u0159\u00edkaz «su hax», kter\u00fd z\u00edsk\u00e1v\u00e1 ne origin\u00e1ln\u00ed datab\u00e1zi u\u017eivatel\u016f z \u00falo\u017ei\u0161t\u011b, ale upravenou kopii s podstr\u010den\u00fdm p\u0159ihla\u0161ov\u00e1n\u00edm «hax», kter\u00e9mu jsou ud\u011blena pr\u00e1va root a pr\u00e1zdn\u00e9 heslo. Fungov\u00e1n\u00ed exploitu bylo otestov\u00e1no v Ubuntu 24.04.
\n
Zdroj: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0412 \u043e\u0442\u043a\u0440\u044b\u0442\u043e\u043c \u0434\u043e\u0441\u0442\u0443\u043f\u0435 \u0440\u0430\u0437\u043c\u0435\u0449\u0451\u043d \u044d\u043a\u0441\u043f\u043b\u043e\u0438\u0442 \u0434\u043b\u044f \u0441\u0435\u0434\u044c\u043c\u043e\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 (1, 2-3, 4, 5, 6) \u0432 \u044f\u0434\u0440\u0435 Linux, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u043d\u0435\u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u043e\u043c\u0443 \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u043e\u043c\u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044e \u043f\u043e\u043b\u0443\u0447\u0438\u0442\u044c \u043f\u0440\u0430\u0432\u0430 root, \u043f\u0435\u0440\u0435\u0437\u0430\u043f\u0438\u0441\u0430\u0432 \u0434\u0430\u043d\u043d\u044b\u0435 \u0432 \u0441\u0442\u0440\u0430\u043d\u0438\u0447\u043d\u043e\u043c \u043a\u044d\u0448\u0435. CVE-\u0438\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440 \u0435\u0449\u0451 \u043d\u0435 \u043f\u0440\u0438\u0441\u0432\u043e\u0435\u043d, \u043a\u0440\u043e\u043c\u0435 \u043a\u043e\u0434\u0430 \u044d\u043a\u0441\u043f\u043b\u043e\u0438\u0442\u0430 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u0438 \u043e \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0435 \u043f\u043e\u043a\u0430 \u043d\u0435\u0442. \u0418\u0441\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u0435 \u0434\u043e\u0441\u0442\u0443\u043f\u043d\u043e \u0442\u043e\u043b\u044c\u043a\u043e \u0432 \u0432\u0438\u0434\u0435 \u043f\u0430\u0442\u0447\u0430, \u043a\u043e\u0442\u043e\u0440\u044b\u0439 \u043e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d 20 \u043c\u0430\u044f \u0438 21 \u043c\u0430\u044f \u0431\u044b\u043b \u043f\u0440\u0438\u043d\u044f\u0442 […]<\/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-181668","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\udd47GRO Frag \u2014 sedm\u00e1 zranitelnost t\u0159\u00eddy Copy Fail, poskytuj\u00edc\u00ed pr\u00e1va roota v Linuxu | ProHoster","description":"Ve ve\u0159ejn\u00e9m prostoru byla zve\u0159ejn\u011bna exploita pro sedmou zranitelnost (1, 2-3, 4, 5, 6) v j\u00e1d\u0159e Linux, kter\u00e1 umo\u017e\u0148uje neprivilegovan\u00e9mu lok\u00e1ln\u00edmu u\u017eivateli z\u00edskat pr\u00e1va roota p\u0159eps\u00e1n\u00edm dat v str\u00e1nkov\u00e9m cache.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/news\/gro-frag-sedmaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","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\udd47GRO Frag \u2014 \u0441\u0435\u0434\u044c\u043c\u0430\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043b\u0430\u0441\u0441\u0430 Copy Fail, \u043f\u0440\u0435\u0434\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u044e\u0449\u0430\u044f \u043f\u0440\u0430\u0432\u0430 root \u0432 Linux | ProHoster","og:description":"\u0412 \u043e\u0442\u043a\u0440\u044b\u0442\u043e\u043c \u0434\u043e\u0441\u0442\u0443\u043f\u0435 \u0440\u0430\u0437\u043c\u0435\u0449\u0451\u043d \u044d\u043a\u0441\u043f\u043b\u043e\u0438\u0442 \u0434\u043b\u044f \u0441\u0435\u0434\u044c\u043c\u043e\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 (1, 2-3, 4, 5, 6) \u0432 \u044f\u0434\u0440\u0435 Linux, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u043d\u0435\u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u043e\u043c\u0443 \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u043e\u043c\u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044e \u043f\u043e\u043b\u0443\u0447\u0438\u0442\u044c \u043f\u0440\u0430\u0432\u0430 root, \u043f\u0435\u0440\u0435\u0437\u0430\u043f\u0438\u0441\u0430\u0432 \u0434\u0430\u043d\u043d\u044b\u0435 \u0432 \u0441\u0442\u0440\u0430\u043d\u0438\u0447\u043d\u043e\u043c \u043a\u044d\u0448\u0435.","og:url":"https:\/\/prohoster.info\/cs\/blog\/news\/gro-frag-sedmaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-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":"2026-05-22T22:25:11+00:00","article:modified_time":"2026-05-22T22:25:11+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\/cs\/wp-json\/wp\/v2\/posts\/181668","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=181668"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/181668\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=181668"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=181668"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=181668"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}