{"id":181809,"date":"2026-05-30T14:48:10","date_gmt":"2026-05-30T12:48:10","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/obnarodovana-lpe-uyazvimost-cifswitch-v-linux-cifs-cifs-utils"},"modified":"2026-05-30T14:48:10","modified_gmt":"2026-05-30T12:48:10","slug":"obnarodovana-lpe-uyazvimost-cifswitch-v-linux-cifs-cifs-utils","status":"publish","type":"post","link":"https:\/\/prohoster.info\/ro\/blog\/news\/obnarodovana-lpe-uyazvimost-cifswitch-v-linux-cifs-cifs-utils","title":{"rendered":"A fost dezv\u0103luit\u0103 vulnerabilitatea LPE CIFSwitch \u00een Linux CIFS\/cifs-utils","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Cercet\u0103tor de securitate Asim Manizada<\/strong> a descoperit o vulnerabilitate CIFSwitch<\/strong> \u2014 escaladarea privilegiilor locale \u00een leg\u0103tura dintre kernelul Linux \u0219i pachetul utilizatorului cifs-utils<\/strong>. Problema afecteaz\u0103 calea de procesare CIFS\/SMB Kerberos\/SPNEGO upcall<\/strong>, adic\u0103 mecanismul prin care clientul CIFS din kernel solicit\u0103 informa\u021bii pentru autentificarea Kerberos de la helper-ul utilizatorului atunci c\u00e2nd monteaz\u0103 resurse SMB. Descrierea a fost publicat\u0103 dup\u0103 expirarea embargoului linux-distros; identificatorul CVE nu fusese \u00eenc\u0103 atribuit la momentul public\u0103rii.<\/p>\n

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Substan\u021ba vulnerabilit\u0103\u021bii este c\u0103<\/a>, ceea ce a permis unui utilizator neprefect s\u0103 invoce request_key("cifs.spnego", …) \u0219i s\u0103 trimit\u0103 o descriere fals\u0103 a cheii. \u00centr-un scenariu normal, aceast\u0103 linie ar trebui s\u0103 fie generat\u0103 de clientul CIFS al nucleului: con\u021bine informa\u021bii despre server, UID, credential UID, PID, obiectivul upcall \u0219i alte parametri. Totu\u0219i, nucleul nu a verificat dac\u0103 descrierea a venit cu adev\u0103rat din subsistemul CIFS, iar cifs.upcall, care este rulat de root prin regula standard request-key, a avut \u00eencredere \u00een aceste c\u00e2mpuri ca fiind date create de nucleu.<\/p>\n

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Vulnerabilitatea nu este o problem\u0103 universal\u0103<\/a> \u201eo bre\u0219\u0103 \u00een orice Linux din fabric\u0103\u201d. Pentru a exploata aceasta, trebuie s\u0103 coincid\u0103 mai multe condi\u021bii: un kernel vulnerabil, cifs-utils instalat cu regula cifs.spnego, capacitatea utilizatorilor f\u0103r\u0103 privilegii de a crea user\/mount namespaces, precum \u0219i absen\u021ba bloc\u0103rilor din partea SELinux, AppArmor sau alt\u0103 politic\u0103 LSM. \u00centr-un anun\u021b pe oss-security, s-a specificat \u00een mod special c\u0103 pe sistemele vulnerabile aceasta ofer\u0103 un traseu de la un utilizator local f\u0103r\u0103 privilegii la executarea de cod din partea root.<\/p>\n

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

Din punct de vedere tehnic lan\u021bul se construie\u0219te \u00een jurul faptului<\/a>, c\u0103 cifs.upcall poate trece \u00een spa\u021biile de nume specificate \u00een descrierea falsificat\u0103 \u0219i efectua o solicitare NSS p\u00e2n\u0103 la resetarea final\u0103 a privilegiilor. Ca rezultat, un mediu controlat de atacator poate influen\u021ba \u00eenc\u0103rcarea modulului NSS de c\u0103tre procesul root. \u00cen descrierile publice se subliniaz\u0103 c\u0103 aceasta este o eroare logic\u0103 la limita dintre kernel \u0219i user space, nu o vulnerabilitate clasic\u0103 de corup\u021bie a memoriei.<\/p>\n

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

Corectarea din kernel s-a dovedit a fi redus\u0103: pentru tipul de chei cifs.spnego a fost ad\u0103ugat\u0103 o verificare care respinge descrierile create nu de clientul CIFS, cu spnego_cred-urile sale private. Aceast\u0103 abordare \u00eenchide un tip de atacuri f\u0103r\u0103 modific\u0103ri sincrone obligatorii \u00een cifs-utils, de\u0219i autorul subliniaz\u0103 c\u0103 \u00eent\u0103rirea suplimentar\u0103 a user space-ului r\u0103m\u00e2ne dorit\u0103.<\/p>\n

<\/p>\n

AlmaLinux a anun\u021bat<\/a>, logic\u0103 de baz\u0103 este prezent\u0103 \u00een toate versiunile acceptate de AlmaLinux, iar AlmaLinux 8, 9, 10 \u0219i Kitten 10 sunt considerate afectate dac\u0103 cifs-utils este instalat. Kernelurile patch-uite au fost preg\u0103tite \u00een repozitoarele testing: pentru AlmaLinux 9, pachetul kernel-5.14.0-687.5.4.el9_8 sau mai recent, iar pentru AlmaLinux 10 \u2014 kernel-6.12.0-211.7.4.el10_2 sau mai recent.<\/p>\n

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

Ca m\u0103sur\u0103 temporar\u0103 p\u00e2n\u0103 la instalarea kernelului corectat, se recomand\u0103 s\u0103 se elimine cifs-utils, dac\u0103 clientul SMB\/CIFS nu este utilizat pe sistem, s\u0103 se interzic\u0103 \u00eenc\u0103rcarea modulului cifs, s\u0103 se redefineasc\u0103 regula cifs.spnego \u00een request-key sau s\u0103 se dezactiveze namespace-urile utilizatorilor neprivilegia\u021bi. Aceste m\u0103suri compensatorii pot afecta autentificarea Kerberos pentru mont\u0103rile CIFS, deci pe servere unde se utilizeaz\u0103 cu adev\u0103rat partaj\u0103rile SMB autentificate Kerberos, acestea trebuie aplicate cu precau\u021bie.<\/p>\n

CIFSwitch este interesant\u0103 \u0219i \u00een contextul descoperirii: autorul o descrie ca rezultat al c\u0103ut\u0103rii lan\u021burilor multi-pa\u0219i utiliz\u00e2nd LLM \u0219i reprezentarea grafic\u0103 a leg\u0103turilor \u00eentre obiecte de securitate. Dar concluzia practic\u0103 pentru administratori este destul de pragmatic\u0103: verificarea prezen\u021bei cifs-utils, a st\u0103rii namespace-urilor utilizatorilor \u0219i a actualiz\u0103rilor kernelului, mai ales pe sistemele unde exist\u0103 utilizatori locali sau scenarii de containere cu capabilit\u0103\u021bi extinse de namespace.<\/p>\n

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

\u0418\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 Asim Manizada \u0440\u0430\u0441\u043a\u0440\u044b\u043b \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c CIFSwitch \u2014 \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u043e\u0435 \u043f\u043e\u0432\u044b\u0448\u0435\u043d\u0438\u0435 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0439 \u0432 \u0441\u0432\u044f\u0437\u043a\u0435 \u044f\u0434\u0440\u0430 Linux \u0438 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u0441\u043a\u043e\u0433\u043e \u043f\u0430\u043a\u0435\u0442\u0430 cifs-utils. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u0437\u0430\u0442\u0440\u0430\u0433\u0438\u0432\u0430\u0435\u0442 \u043f\u0443\u0442\u044c \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 CIFS\/SMB Kerberos\/SPNEGO upcall, \u0442\u043e \u0435\u0441\u0442\u044c \u043c\u0435\u0445\u0430\u043d\u0438\u0437\u043c, \u0447\u0435\u0440\u0435\u0437 \u043a\u043e\u0442\u043e\u0440\u044b\u0439 CIFS-\u043a\u043b\u0438\u0435\u043d\u0442 \u044f\u0434\u0440\u0430 \u0437\u0430\u043f\u0440\u0430\u0448\u0438\u0432\u0430\u0435\u0442 \u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u0441\u043a\u043e\u0433\u043e helper\u2019\u0430 \u0434\u0430\u043d\u043d\u044b\u0435 \u0434\u043b\u044f Kerberos-\u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438 \u043f\u0440\u0438 \u043c\u043e\u043d\u0442\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0438 SMB-\u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432. \u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u043e \u043f\u043e\u0441\u043b\u0435 \u0438\u0441\u0442\u0435\u0447\u0435\u043d\u0438\u044f \u044d\u043c\u0431\u0430\u0440\u0433\u043e linux-distros; \u0438\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440 CVE \u043d\u0430 \u043c\u043e\u043c\u0435\u043d\u0442 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438 \u0435\u0449\u0451 […]<\/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-181809","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\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\udd47A fost publicat\u0103 vulnerabilitatea LPE CIFSwitch \u00een Linux CIFS\/cifs-utils | ProHoster","description":"Cercet\u0103torul de securitate Asim Manizada a dezv\u0103luit vulnerabilitatea CIFSwitch \u2014 escaladarea privilegiilor locale \u00een combina\u021bia kernelului Linux \u0219i a pachetului de utilizator cifs-utils.","canonical_url":"https:\/\/prohoster.info\/ro\/blog\/news\/obnarodovana-lpe-uyazvimost-cifswitch-v-linux-cifs-cifs-utils","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"ro_RO","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\u041e\u0431\u043d\u0430\u0440\u043e\u0434\u043e\u0432\u0430\u043d\u0430 LPE-\u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c CIFSwitch \u0432 Linux CIFS\/cifs-utils | ProHoster","og:description":"\u0418\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 Asim Manizada \u0440\u0430\u0441\u043a\u0440\u044b\u043b \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c CIFSwitch \u2014 \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u043e\u0435 \u043f\u043e\u0432\u044b\u0448\u0435\u043d\u0438\u0435 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0439 \u0432 \u0441\u0432\u044f\u0437\u043a\u0435 \u044f\u0434\u0440\u0430 Linux \u0438 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u0441\u043a\u043e\u0433\u043e \u043f\u0430\u043a\u0435\u0442\u0430 cifs-utils.","og:url":"https:\/\/prohoster.info\/ro\/blog\/news\/obnarodovana-lpe-uyazvimost-cifswitch-v-linux-cifs-cifs-utils","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":"2026-05-30T12:48:10+00:00","article:modified_time":"2026-05-30T12:48:10+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\/ro\/wp-json\/wp\/v2\/posts\/181809","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/comments?post=181809"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts\/181809\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/media?parent=181809"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/categories?post=181809"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/tags?post=181809"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}