{"id":105506,"date":"2022-11-09T03:36:39","date_gmt":"2022-11-09T01:36:39","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/uyazvimost-v-proshivkah-uefi-pozvolyayushhaya-vypolnit-kod-na-urovne-smm"},"modified":"2022-11-09T03:36:39","modified_gmt":"2022-11-09T01:36:39","slug":"uyazvimost-v-proshivkah-uefi-pozvolyayushhaya-vypolnit-kod-na-urovne-smm","status":"publish","type":"post","link":"https:\/\/prohoster.info\/it\/blog\/novosti-interneta\/uyazvimost-v-proshivkah-uefi-pozvolyayushhaya-vypolnit-kod-na-urovne-smm","title":{"rendered":"Vulnerability in UEFI firmware that allows code execution at the SMM level.","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

\u00c8 stata rivelata un'informazione su una vulnerabilit\u00e0 (CVE-2021-33164) nei firmware UEFI, che consente l'esecuzione di codice a livello SMM (System Management Mode), un livello di priorit\u00e0 superiore a quello del hypervisor e del ring zero, offrendo accesso illimitato a tutta la memoria di sistema. La vulnerabilit\u00e0, denominata RingHopper, \u00e8 collegata alla possibilit\u00e0 di eseguire un attacco temporale tramite DMA (Direct Memory Access) per compromettere la memoria del codice in esecuzione a livello SMM. \u00c8 stata confermata la presenza della vulnerabilit\u00e0 nei firmware di Intel, Dell e Insyde Software (si sostiene che il problema coinvolga 8 produttori, ma gli altri 5 non sono ancora stati rivelati). I firmware AMD, Phoenix e Toshiba non sono affetti dal problema. <\/p>\n

L'utilizzo delle vulnerabilit\u00e0 pu\u00f2 avvenire dal sistema operativo, utilizzando gestori SMI vulnerabili (System Management Interrupt), ai quali \u00e8 necessario avere diritti di amministratore per accedere. L'attacco pu\u00f2 essere effettuato anche in presenza di accesso fisico nella fase iniziale di avvio, prima dell'inizializzazione del sistema operativo. Per mitigare il problema, si raccomanda agli utenti Linux di aggiornare il firmware tramite il servizio LVFS (Linux Vendor Firmware Service), utilizzando l'utilit\u00e0 fwupdmgr (fwupdmgr get-updates; fwupdmgr update) del pacchetto fwupd. <\/p>\n

La necessit\u00e0 di avere diritti di amministratore per eseguire un attacco limita il rischio del problema, ma non impedisce il suo utilizzo come vulnerabilit\u00e0 di secondo livello, per mantenere la propria presenza dopo aver sfruttato altre vulnerabilit\u00e0 nel sistema o aver applicato metodi di ingegneria sociale. L'accesso al SMM (Ring -2) consente di eseguire codice a un livello non controllabile dal sistema operativo, il che pu\u00f2 essere utilizzato per modificare i firmware e inserire codici dannosi o rootkit nello SPI Flash, che non possono essere rilevati dal sistema operativo, cos\u00ec come per disabilitare la verifica durante il caricamento (UEFI Secure Boot, Intel BootGuard) e per attacchi ai hypervisor per aggirare i meccanismi di verifica dell'integrit\u00e0 degli ambienti virtuali. <\/p>\n

Il problema \u00e8 causato da una condizione di competizione nel gestore SMI (System Management Interrupt), che si verifica nel momento tra il controllo dell'accesso e l'accesso a SMRAM. Per determinare il momento opportuno tra la verifica dello stato e l'utilizzo del risultato della verifica, pu\u00f2 essere utilizzata un'analisi attraverso canali esterni tramite DMA. Di conseguenza, a causa della natura asincrona dell'accesso a SMRAM attraverso DMA, un attaccante pu\u00f2 determinare il momento necessario e sovrascrivere il contenuto di SMRAM utilizzando DMA per aggirare le API del gestore SMI. I processori con supporto per le tecnologie Intel-VT e Intel VT-d includono protezione contro attacchi DMA, basata sull'uso dell'IOMMU (Input-Output Memory Management Unit), ma questa protezione \u00e8 efficace per bloccare attacchi hardware DMA condotti da dispositivi preparati dall'attaccante, e non protegge da attacchi tramite gestori SMI.
\n
Fonte: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0420\u0430\u0441\u043a\u0440\u044b\u0442\u0430 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 (CVE-2021-33164) \u0432 \u043f\u0440\u043e\u0448\u0438\u0432\u043a\u0430\u0445 UEFI, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 SMM (System Management Mode), \u0431\u043e\u043b\u0435\u0435 \u043f\u0440\u0438\u043e\u0440\u0438\u0442\u0435\u0442\u043d\u043e\u043c, \u0447\u0435\u043c \u0440\u0435\u0436\u0438\u043c \u0433\u0438\u043f\u0435\u0440\u0432\u0438\u0437\u043e\u0440\u0430 \u0438 \u043d\u0443\u043b\u0435\u0432\u043e\u0435 \u043a\u043e\u043b\u044c\u0446\u043e \u0437\u0430\u0449\u0438\u0442\u044b, \u0438 \u043f\u0440\u0435\u0434\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u044e\u0449\u0435\u043c \u043d\u0435\u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u043d\u044b\u0439 \u0434\u043e\u0441\u0442\u0443\u043f \u043a\u043e \u0432\u0441\u0435\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043f\u043e\u043b\u0443\u0447\u0438\u043b\u0430 \u043a\u043e\u0434\u043e\u0432\u043e\u0435 \u0438\u043c\u044f RingHopper, \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u0432\u043e\u0437\u043c\u043e\u0436\u043d\u043e\u0441\u0442\u044c\u044e \u043f\u0440\u043e\u0432\u0435\u0434\u0435\u043d\u0438\u044f \u0430\u0442\u0430\u043a\u0438 \u043f\u043e \u0432\u0440\u0435\u043c\u0435\u043d\u0438 \u043f\u0440\u0438 \u043f\u043e\u043c\u043e\u0449\u0438 DMA (Direct Memory Access) \u0434\u043b\u044f \u043f\u043e\u0432\u0440\u0435\u0436\u0434\u0435\u043d\u0438\u044f […]<\/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-105506","post","type-post","status-publish","format-standard","hentry","category-novosti-interneta"],"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\udd47 Vulnerabilit\u00e0 nei firmware UEFI che consente l'esecuzione di codice a livello di SMM | ProHoster","description":"\u00c8 stata rivelata un'informazione su una vulnerabilit\u00e0 (CVE-2021-33164) nei firmware UEFI, che consente di eseguire codice a livello di SMM (System Management Mode), un livello di priorit\u00e0 superiore a quello di hypervisor e dell'anello zero di protezione, fornendo accesso illimitato a tutta la memoria di sistema. Questa vulnerabilit\u00e0, soprannominata RingHopper, \u00e8 legata alla possibilit\u00e0 di un attacco temporale tramite DMA (Direct Memory Access) per compromettere.","canonical_url":"https:\/\/prohoster.info\/it\/blog\/novosti-interneta\/uyazvimost-v-proshivkah-uefi-pozvolyayushhaya-vypolnit-kod-na-urovne-smm","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"it_IT","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\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432 \u043f\u0440\u043e\u0448\u0438\u0432\u043a\u0430\u0445 UEFI, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 SMM | ProHoster","og:description":"\u0420\u0430\u0441\u043a\u0440\u044b\u0442\u0430 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 (CVE-2021-33164) \u0432 \u043f\u0440\u043e\u0448\u0438\u0432\u043a\u0430\u0445 UEFI, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043a\u043e\u0434 \u043d\u0430 \u0443\u0440\u043e\u0432\u043d\u0435 SMM (System Management Mode), \u0431\u043e\u043b\u0435\u0435 \u043f\u0440\u0438\u043e\u0440\u0438\u0442\u0435\u0442\u043d\u043e\u043c, \u0447\u0435\u043c \u0440\u0435\u0436\u0438\u043c \u0433\u0438\u043f\u0435\u0440\u0432\u0438\u0437\u043e\u0440\u0430 \u0438 \u043d\u0443\u043b\u0435\u0432\u043e\u0435 \u043a\u043e\u043b\u044c\u0446\u043e \u0437\u0430\u0449\u0438\u0442\u044b, \u0438 \u043f\u0440\u0435\u0434\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u044e\u0449\u0435\u043c \u043d\u0435\u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u043d\u044b\u0439 \u0434\u043e\u0441\u0442\u0443\u043f \u043a\u043e \u0432\u0441\u0435\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u043f\u043e\u043b\u0443\u0447\u0438\u043b\u0430 \u043a\u043e\u0434\u043e\u0432\u043e\u0435 \u0438\u043c\u044f RingHopper, \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u0432\u043e\u0437\u043c\u043e\u0436\u043d\u043e\u0441\u0442\u044c\u044e \u043f\u0440\u043e\u0432\u0435\u0434\u0435\u043d\u0438\u044f \u0430\u0442\u0430\u043a\u0438 \u043f\u043e \u0432\u0440\u0435\u043c\u0435\u043d\u0438 \u043f\u0440\u0438 \u043f\u043e\u043c\u043e\u0449\u0438 DMA (Direct Memory Access) \u0434\u043b\u044f \u043f\u043e\u0432\u0440\u0435\u0436\u0434\u0435\u043d\u0438\u044f","og:url":"https:\/\/prohoster.info\/it\/blog\/novosti-interneta\/uyazvimost-v-proshivkah-uefi-pozvolyayushhaya-vypolnit-kod-na-urovne-smm","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":"2022-11-09T01:36:39+00:00","article:modified_time":"2022-11-09T01:36:39+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\/it\/wp-json\/wp\/v2\/posts\/105506","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/comments?post=105506"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/posts\/105506\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/media?parent=105506"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/categories?post=105506"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/it\/wp-json\/wp\/v2\/tags?post=105506"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}