{"id":172665,"date":"2026-05-19T00:24:34","date_gmt":"2026-05-18T22:24:34","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/dirtydecrypt-ocherednaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux"},"modified":"2026-05-19T00:24:34","modified_gmt":"2026-05-18T22:24:34","slug":"dirtydecrypt-ocherednaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","status":"publish","type":"post","link":"https:\/\/prohoster.info\/hr\/blog\/news\/dirtydecrypt-ocherednaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","title":{"rendered":"DirtyDecrypt \u2014 nova ranjivost klase Copy Fail, koja omogu\u0107uje root pristup u Linuxu","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

U Linux kernelu otkrivena je ranjivost koja, na sli\u010dan na\u010din kao i ranjivosti Copy Fail, Dirty Frag i Fragnesia, omogu\u0107uje neprivilegiranom korisniku da dobije root prava prepisivanjem podataka u stranici ke\u0161a. Ranjivosti je dodijeljeno kodno ime DirtyDecrypt (problem se tako\u0111er spominje pod imenom DirtyCBC). Dostupan je prototip eksploita. <\/p>\n

CVE identifikator u napomeni o eksploitu nije spomenut, navedeno je samo da su istra\u017eiva\u010di otkrili problem 9. svibnja, nakon \u010dega su obavijestili programere jezgre, koji su odgovorili da njihovo otkri\u0107e duplicira drugi izvje\u0161taj o ve\u0107 ispravljenoj ranjivosti. Kako je zakrpa sa rje\u0161enjem ve\u0107 uklju\u010dena u jezgru, istra\u017eiva\u010di su odlu\u010dili objaviti eksploat. Sude\u0107i prema opisu unutar eksploita, koristi se ranjivost CVE-2026-31635, \u010dije je rje\u0161enje prihva\u0107eno u jezgru u travnju i uklju\u010deno u verziju 7.0.0 i formiranu izdanje 6.18.23 od 18. travnja. Problem se pojavljuje po\u010dev\u0161i od jezgre 6.16. <\/p>\n

Kao i u slu\u010daju Dirty Frag serije ranjivosti, nova ranjivost se nalazi u RxRPC upravlja\u010dkom programu, koji implementira AF_RXRPC socket porodicu i odgovaraju\u0107i RPC protokol koji radi preko UDP-a. Problem je uzrokovan gre\u0161kom u provjeri veli\u010dine podataka u funkciji rxgk_verify_response() \u2014 umjesto provjere 'if (auth_len > len)', u kodu je bila navedena 'if (auth_len < len)', \u0161to je dovelo do slanja prevelikih podataka u funkciju rxgk_decrypt_skb(). Kada se izvr\u0161ava funkcija rxgk_decrypt_skb(), de\u0161ifriranje podataka vr\u0161i se s umetnutim promjenama direktno u stranicu predmemorije kako bi se izbjeglo dodatno kori\u0161tenje bafera. Zbog pogre\u0161ne provjere veli\u010dine, postojala je mogu\u0107nost prepisivanja podataka u predmemoriji stranice na odabranom pomaku. <\/p>\n

Eksploatacija ranjivosti svodi se na \u010ditanje datoteke programa s suid root zastavicom (radi njenog smje\u0161tanja u stranicu predmemorije) i zamjenu dijela koda programa u predmemoriji koda za pokretanje \/usr\/bin\/sh. Naknadno pokretanje programa rezultirat \u0107e time da \u0107e u memoriju biti u\u010ditan neoriginalni izvr\u0161ni datoteka s ure\u0111aja, ve\u0107 izmijenjena kopija iz predmemorije stranice. Kao suid programi u eksploitu su predvi\u0111ene mogu\u0107nosti kori\u0161tenja '\/usr\/bin\/su', '\/bin\/su', '\/usr\/bin\/mount', '\/usr\/bin\/passwd' i '\/usr\/bin\/chsh'. <\/p>\n

Za iskori\u0161tavanje ranjivosti prilikom kompajliranja jezgre mora biti aktivna opcija CONFIG_RXGK, a za automatsko u\u010ditavanje dostupan modul jezgre rxrpc.ko (u nekim sustavima se ne kompajlira). Status ispravka ranjivosti u distribucijama mo\u017ee se procijeniti na sljede\u0107im stranicama: Debian, Ubuntu, SUSE\/openSUSE, RHEL, Arch, Fedora. Kao zaobilazno rje\u0161enje za\u0161tite mo\u017ee se blokirati u\u010ditavanje modula jezgre rxrpc: <\/p>\n

sh -c 'printf 'install rxrpc \/bin\/false\n' > \/etc\/modprobe.d\/dirtydecrypt.conf; rmmod rxrpc 2>\/dev\/null; true' <\/p>\n

Dodatno se mo\u017ee primijetiti objava u mailing listi developerskog tima Linux jezgra zakrpa koje potpuno isklju\u010duju optimizacije u crypto API (AF_ALG) koje koriste direktan pristup predmemoriji stranica prilikom de\u0161ifriranja pomo\u0107u algoritama 'skcipher' i 'aead'. Ove optimizacije isklju\u010duju dodatno kori\u0161tenje bafera podataka, ali stvaraju rizike od ozbiljnih ranjivosti. Pretpostavlja se da \u0107e njihovo isklju\u010divanje dovesti samo do neznatnog smanjenja performansi zbog dodatne operacije kopiranja u zasebni bafer. Zakrpe su prihva\u0107ene od strane onih koji prate crypto API podsklopa i uklju\u010dene su u 'cryptodev' granu, gdje se razvijaju mogu\u0107nosti za uklju\u010divanje u glavni sastav budu\u0107ih izdanja Linux jezgra.
\n
Izvor: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0412 \u044f\u0434\u0440\u0435 Linux \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043f\u043e \u0430\u043d\u0430\u043b\u043e\u0433\u0438\u0438 \u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044f\u043c\u0438 Copy Fail, Dirty Frag \u0438 Fragnesia \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \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 \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. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043f\u0440\u0438\u0441\u0432\u043e\u0435\u043d\u043e \u043a\u043e\u0434\u043e\u0432\u043e\u0435 \u0438\u043c\u044f DirtyDecrypt (\u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u0442\u0430\u043a\u0436\u0435 \u0443\u043f\u043e\u043c\u0438\u043d\u0430\u0435\u0442\u0441\u044f \u043f\u043e\u0434 \u0438\u043c\u0435\u043d\u0435\u043c DirtyCBC). \u0414\u043e\u0441\u0442\u0443\u043f\u0435\u043d \u043f\u0440\u043e\u0442\u043e\u0442\u0438\u043f \u044d\u043a\u0441\u043f\u043b\u043e\u0438\u0442\u0430. CVE-\u0438\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440 \u0432 \u043f\u0440\u0438\u043c\u0435\u0447\u0430\u043d\u0438\u0438 \u043a \u044d\u043a\u0441\u043f\u043b\u043e\u0438\u0442\u0443 \u043d\u0435 \u0443\u043f\u043e\u043c\u0438\u043d\u0430\u0435\u0442\u0441\u044f, \u0443\u043a\u0430\u0437\u0430\u043d\u043e \u043b\u0438\u0448\u044c, \u0447\u0442\u043e \u0438\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u0438 \u0432\u044b\u044f\u0432\u0438\u043b\u0438 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0443 9 \u043c\u0430\u044f, […]<\/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-172665","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\udd47DirtyDecrypt \u2014 jo\u0161 jedna ranjivost klase Copy Fail, koja osigurava root prava u Linuxu | ProHoster","description":"U jezgru Linux otkrivena je ranjivost, koja, analogno ranjivostima Copy Fail, Dirty Frag i Fragnesia, omogu\u0107ava neprivilegiranom korisniku da dobije root prava prepisivanjem podataka u stranici ke\u0161a.","canonical_url":"https:\/\/prohoster.info\/hr\/blog\/news\/dirtydecrypt-ocherednaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","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\udd47DirtyDecrypt \u2014 \u043e\u0447\u0435\u0440\u0435\u0434\u043d\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 \u044f\u0434\u0440\u0435 Linux \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043f\u043e \u0430\u043d\u0430\u043b\u043e\u0433\u0438\u0438 \u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044f\u043c\u0438 Copy Fail, Dirty Frag \u0438 Fragnesia \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \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 \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\/hr\/blog\/news\/dirtydecrypt-ocherednaya-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":"2026-05-18T22:24:34+00:00","article:modified_time":"2026-05-18T22:24:34+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\/172665","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\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/comments?post=172665"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/posts\/172665\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/media?parent=172665"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/categories?post=172665"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/tags?post=172665"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}