{"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\/hu\/blog\/news\/dirtydecrypt-ocherednaya-uyazvimost-klassa-copy-fail-predostavlyayushhaya-prava-root-v-linux","title":{"rendered":"DirtyDecrypt \u2014 egy \u00fajabb Copy Fail oszt\u00e1ly\u00fa s\u00e9r\u00fcl\u00e9kenys\u00e9g, amely root jogokat biztos\u00edt a Linuxban","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

A Linux kernelj\u00e9ben fedeztek fel egy s\u00e9r\u00fcl\u00e9kenys\u00e9get, amely a Copy Fail, Dirty Frag \u00e9s Fragnesia s\u00e9r\u00fcl\u00e9kenys\u00e9gekhez hasonl\u00f3an lehet\u0151v\u00e9 teszi, hogy egy nem privilegiz\u00e1lt felhaszn\u00e1l\u00f3 root jogokat szerezzen az\u00e1ltal, hogy adatokat \u00edr fel\u00fcl az oldalgyorst\u00e1rban. A s\u00e9r\u00fcl\u00e9kenys\u00e9g k\u00f3dneve DirtyDecrypt (a probl\u00e9ma DirtyCBC n\u00e9ven is ismert). El\u00e9rhet\u0151 egy exploit protot\u00edpus. <\/p>\n

A CVE azonos\u00edt\u00f3t az exploit jegyzet\u00e9ben nem eml\u00edtik, csak annyit jeleztek, hogy a kutat\u00f3k m\u00e1jus 9-\u00e9n fedezt\u00e9k fel a probl\u00e9m\u00e1t, majd \u00e9rtes\u00edtett\u00e9k a kernel fejleszt\u0151it, akik azt v\u00e1laszolt\u00e1k, hogy a felfedez\u00e9s\u00fck egy m\u00e1sik, m\u00e1r jav\u00edtott s\u00e9r\u00fcl\u00e9kenys\u00e9gr\u0151l k\u00e9sz\u00fclt jelent\u00e9s duplik\u00e1tuma. Mivel a jav\u00edt\u00f3program m\u00e1r be volt \u00e9p\u00edtve a kernelbe, a kutat\u00f3k \u00fagy d\u00f6nt\u00f6ttek, hogy k\u00f6zz\u00e9teszik az \u00e1ltaluk kidolgozott exploitot. Az exploit le\u00edr\u00e1sa szerint a CVE-2026-31635 s\u00e9r\u00fcl\u00e9kenys\u00e9get haszn\u00e1lja, amelynek jav\u00edt\u00e1s\u00e1t \u00e1prilisban fogadt\u00e1k el a kernelbe \u00e9s a 7.0.0 verzi\u00f3t alkot\u00f3 6.18.23 kiad\u00e1s keret\u00e9be is be\u00e9p\u00edtett\u00e9k. A probl\u00e9ma a 6.16 \u00e1gb\u00f3l kezd\u0151d\u0151en jelentkezik. <\/p>\n

A Dirty Frag s\u00e9ria sehez hasonl\u00f3an az \u00faj sebezhet\u0151s\u00e9g az RxRPC drivert \u00e9rinti, amely az AF_RXRPC socketcsal\u00e1dot \u00e9s a hozz\u00e1 tartoz\u00f3 RPC protokollt val\u00f3s\u00edtja meg az UDP felett. A probl\u00e9ma a rxgk_verify_response() f\u00fcggv\u00e9nyben fell\u00e9p\u0151 hiba miatt alakult ki, ahol a k\u00f3d nem a helyes «if (auth_len > len)» ellen\u0151rz\u00e9st alkalmazta, hanem «if (auth_len < len)» \u00e1llapotban volt, ami a rxgk_decrypt_skb() f\u00fcggv\u00e9nybe t\u00e9nylegesen t\u00fal nagy m\u00e9ret\u0171 adatokat juttatott. Az rxgk_decrypt_skb() f\u00fcggv\u00e9ny v\u00e9grehajt\u00e1sa sor\u00e1n az adatokat k\u00f6zvetlen\u00fcl a lapcache-be \u00edrt\u00e1k be a felesleges pufferez\u00e9s elker\u00fcl\u00e9se \u00e9rdek\u00e9ben. A helytelen m\u00e9retellen\u0151rz\u00e9s miatt lehet\u0151s\u00e9g ny\u00edlt arra, hogy az adatokra a lapcache-hez v\u00e1lasztott eltol\u00e1ssal \u00edr\u00e1s t\u00f6rt\u00e9njen. <\/p>\n

A sebezhet\u0151s\u00e9g kihaszn\u00e1l\u00e1sa a s\u00faid root jellel rendelkez\u0151 programf\u00e1jl olvas\u00e1s\u00e1ra \u00e9s a lapcache-ben a program egy r\u00e9sz\u00e9nek k\u00f3d\u00e1nak «\/usr\/bin\/sh» k\u00f3dra t\u00f6rt\u00e9n\u0151 cser\u00e9j\u00e9re \u00e9p\u00fcl. A program k\u00f6vetkez\u0151 futtat\u00e1sa eset\u00e9n a mem\u00f3ri\u00e1ba nem az eredeti v\u00e9grehajthat\u00f3 f\u00e1jl ker\u00fcl bet\u00f6lt\u00e9sre az adatt\u00e1rol\u00f3b\u00f3l, hanem a lapcache-b\u0151l sz\u00e1rmaz\u00f3 megv\u00e1ltozott m\u00e1solat. A kihaszn\u00e1l\u00e1si lehet\u0151s\u00e9gek k\u00f6z\u00f6tt szerepel a «\/usr\/bin\/su», «\/bin\/su», «\/usr\/bin\/mount», «\/usr\/bin\/passwd» \u00e9s «\/usr\/bin\/chsh» haszn\u00e1lata. <\/p>\n

A sebezhet\u0151s\u00e9g kihaszn\u00e1l\u00e1s\u00e1hoz a kernel ford\u00edt\u00e1sakor a CONFIG_RXGK opci\u00f3t enged\u00e9lyezni kell, \u00e9s az automatikus ind\u00edt\u00e1shoz el\u00e9rhet\u0151nek kell lennie az rxrpc.ko kernelmodulnak (bizonyos rendszereken nem fordul le). A sebezhet\u0151s\u00e9gek jav\u00edt\u00e1sainak \u00e1llapota a disztrib\u00faci\u00f3kban az al\u00e1bbi oldalakon \u00e9rt\u00e9kelhet\u0151: Debian, Ubuntu, SUSE\/openSUSE, RHEL, Arch, Fedora. V\u00e9delmi \u00e1tmeneti megold\u00e1sk\u00e9nt letilthatjuk az rxrpc kernelmodul bet\u00f6lt\u00e9s\u00e9t: <\/p>\n

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

Tov\u00e1bbi j\u00f3 h\u00edr, hogy megjelentek a Linux kernel fejleszt\u0151i levelez\u0151list\u00e1j\u00e1n olyan patch-ek, amelyek teljesen letiltj\u00e1k a crypto API (AF_ALG) optimaliz\u00e1ci\u00f3it, amelyek k\u00f6zvetlen lapcache haszn\u00e1lat\u00e1val t\u00f6rt\u00e9nik a dek\u00f3dol\u00e1s sor\u00e1n az «skcipher» \u00e9s az «aead» algoritmusokkal. Az optimaliz\u00e1ci\u00f3k elker\u00fclik a felesleges adatok pufferez\u00e9s\u00e9t, de komoly sebezhet\u0151s\u00e9gek kock\u00e1zat\u00e1t teremtik. A patch-ek aktiv\u00e1l\u00e1sa csak minim\u00e1lis teljes\u00edtm\u00e9nycs\u00f6kken\u00e9st eredm\u00e9nyez, mivel plusz egy adatm\u00e1sol\u00e1si m\u0171velet ker\u00fcl bevezet\u00e9sre egy k\u00fcl\u00f6n puffers\u00e1vba. A patch-eket a crypto API-t t\u00e1mogat\u00f3 k\u00f6zz\u00e9tett\u00e9k, \u00e9s beker\u00fcltek a «cryptodev» \u00e1gba, ahol a Linux kernel j\u00f6v\u0151beli kiad\u00e1si opci\u00f3i fejleszt\u00e9s alatt \u00e1llnak.
\n
Forr\u00e1s: 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 egy \u00fajabb Copy Fail oszt\u00e1ly\u00fa sebezhet\u0151s\u00e9g, amely root jogosults\u00e1gokat biztos\u00edt Linuxon | ProHoster","description":"A Linux kernelben felfedeztek egy olyan sebezhet\u0151s\u00e9get, amely a Copy Fail, Dirty Frag \u00e9s Fragnesia sebezhet\u0151s\u00e9gekkel anal\u00f3g m\u00f3don lehet\u0151v\u00e9 teszi egy nem privil\u00e9giz\u00e1lt felhaszn\u00e1l\u00f3 sz\u00e1m\u00e1ra, hogy root jogosults\u00e1gokat szerezzen az oldal cache-ben l\u00e9v\u0151 adatok fel\u00fcl\u00edr\u00e1s\u00e1val.","canonical_url":"https:\/\/prohoster.info\/hu\/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":"hu_HU","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\/hu\/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\/hu\/wp-json\/wp\/v2\/posts\/172665","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/comments?post=172665"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/posts\/172665\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/media?parent=172665"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/categories?post=172665"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/hu\/wp-json\/wp\/v2\/tags?post=172665"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}