Byla zve\u0159ejn\u011bna informace o zranitelnosti (CVE-2023-4001) v z\u00e1plat\u00e1ch pro bootloader GRUB2, kter\u00e9 p\u0159ipravila spole\u010dnost Red Hat. Zranitelnost umo\u017e\u0148uje na mnoha syst\u00e9mech s UEFI obej\u00edt kontrolu hesla nastaven\u00e9ho v GRUB2, kter\u00e9 omezuje p\u0159\u00edstup k nab\u00eddce nabootov\u00e1n\u00ed nebo p\u0159\u00edkazov\u00e9mu \u0159\u00e1dku bootloaderu. Zranitelnost byla zp\u016fsobena zm\u011bnou p\u0159idanou spole\u010dnost\u00ed Red Hat do bal\u00ed\u010dku GRUB2 dod\u00e1van\u00e9ho v RHEL a Fedora Linux. Probl\u00e9m se neprojevuje v hlavn\u00edm projektu GRUB2 a t\u00fdk\u00e1 se pouze distribuc\u00ed, kter\u00e9 pou\u017eily dodate\u010dn\u00e9 z\u00e1platy Red Hat. <\/p>\n
Probl\u00e9m je zp\u016fsoben chybou v logice pou\u017e\u00edv\u00e1n\u00ed UUID pro vyhled\u00e1v\u00e1n\u00ed zav\u00e1d\u011b\u010dem za\u0159\u00edzen\u00ed s konfigura\u010dn\u00edm souborem (nap\u0159\u00edklad \u201e\/boot\/efi\/EFI\/fedora\/grub.cfg\u201c), kter\u00fd obsahuje hash hesla. Aby se obch\u00e1zela autentizace, m\u016f\u017ee u\u017eivatel s fyzick\u00fdm p\u0159\u00edstupem k po\u010d\u00edta\u010di p\u0159ipojit extern\u00ed pam\u011b\u0165, jako je USB Flash, a nastavit pro ni UUID, kter\u00fd se shoduje s identifik\u00e1torem zav\u00e1d\u011bc\u00edho odd\u00edlu \/boot napaden\u00e9ho syst\u00e9mu. <\/p>\n
Mnoho syst\u00e9m\u016f UEFI nejprve zpracov\u00e1v\u00e1 extern\u00ed pam\u011bti a \u0159ad\u00ed je v seznamu zji\u0161t\u011bn\u00fdch za\u0159\u00edzen\u00ed p\u0159ed stacion\u00e1rn\u00edmi pam\u011btmi, tak\u017ee p\u0159i zpracov\u00e1n\u00ed bude prioritn\u011bj\u0161\u00ed odd\u00edl \/boot p\u0159ipraven\u00fd \u00fato\u010dn\u00edkem a GRUB2 se pokus\u00ed na\u010d\u00edst konfigura\u010dn\u00ed soubor z tohoto odd\u00edlu. B\u011bhem vyhled\u00e1v\u00e1n\u00ed odd\u00edlu pomoc\u00ed p\u0159\u00edkazu \u201esearch\u201c v GRUB2 se prov\u00e1d\u00ed ur\u010den\u00ed pouze prvn\u00edho shoduj\u00edc\u00edho se UUID, po kter\u00e9m se vyhled\u00e1v\u00e1n\u00ed zastav\u00ed. Pokud v konkr\u00e9tn\u00edm odd\u00edlu nebude nalezen hlavn\u00ed konfigura\u010dn\u00ed soubor, GRUB2 zobraz\u00ed p\u0159\u00edkazov\u00fd \u0159\u00e1dek, kter\u00fd umo\u017en\u00ed plnou kontrolu nad dal\u0161\u00edm procesem zav\u00e1d\u011bn\u00ed. <\/p>\n
K ur\u010den\u00ed UUID odd\u00edlu m\u016f\u017ee m\u00edstn\u00ed nep\u0159ihla\u0161ovan\u00fd u\u017eivatel pou\u017e\u00edt n\u00e1stroj \u201elsblk\u201c, av\u0161ak ciz\u00ed u\u017eivatel, kter\u00fd nem\u00e1 p\u0159\u00edstup k syst\u00e9mu, ale m\u016f\u017ee sledovat proces zav\u00e1d\u011bn\u00ed, m\u016f\u017ee v n\u011bkter\u00fdch distribuc\u00edch zjistit UUID ze zobrazovan\u00fdch diagnostick\u00fdch zpr\u00e1v b\u011bhem zav\u00e1d\u011bn\u00ed. Zranitelnost byla odstran\u011bna spole\u010dnost\u00ed Red Hat p\u0159id\u00e1n\u00edm nov\u00e9 argumentace k p\u0159\u00edkazu \u201esearch\u201c, kter\u00e1 omezuje skenov\u00e1n\u00ed UUID pouze na blokov\u00e1 za\u0159\u00edzen\u00ed pou\u017e\u00edvan\u00e1 k spu\u0161t\u011bn\u00ed zav\u00e1d\u011b\u010de (tj. odd\u00edl \/boot by m\u011bl b\u00fdt pouze na stejn\u00e9m disku jako syst\u00e9mov\u00fd odd\u00edl EFI). \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-2023-4001) \u0432 \u043f\u0430\u0442\u0447\u0430\u0445 \u043a \u0437\u0430\u0433\u0440\u0443\u0437\u0447\u0438\u043a\u0443 GRUB2, \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d\u043d\u044b\u0445 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0435\u0439 Red Hat. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u0435\u0442 \u043d\u0430 \u043c\u043d\u043e\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c\u0430\u0445 \u0441 UEFI \u043e\u0431\u043e\u0439\u0442\u0438 \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u0443 \u043f\u0430\u0440\u043e\u043b\u044f, \u0432\u044b\u0441\u0442\u0430\u0432\u043b\u0435\u043d\u043d\u043e\u0433\u043e \u0432 GRUB2 \u0434\u043b\u044f \u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u0438\u044f \u0434\u043e\u0441\u0442\u0443\u043f\u0430 \u043a \u0437\u0430\u0433\u0440\u0443\u0437\u043e\u0447\u043d\u043e\u043c\u0443 \u043c\u0435\u043d\u044e \u0438\u043b\u0438 \u043a\u043e\u043c\u0430\u043d\u0434\u043d\u043e\u0439 \u0441\u0442\u0440\u043e\u043a\u0435 \u0437\u0430\u0433\u0440\u0443\u0437\u0447\u0438\u043a\u0430. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432\u044b\u0437\u0432\u0430\u043d\u0430 \u0438\u0437\u043c\u0435\u043d\u0435\u043d\u0438\u0435\u043c, \u0434\u043e\u0431\u0430\u0432\u043b\u0435\u043d\u043d\u044b\u043c \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0435\u0439 Red Hat \u0432 \u043f\u0430\u043a\u0435\u0442 \u0441 GRUB2, \u043f\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u043c\u044b\u0439 \u0432 RHEL \u0438 Fedora Linux. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 […]<\/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-112924","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\udd47Zranitelnost v patchech Red Hat k zav\u00e1d\u011b\u010di GRUB2, kter\u00e1 umo\u017e\u0148uje obej\u00edt ov\u011b\u0159ov\u00e1n\u00ed hesla | ProHoster","description":"Byla odhalena zranitelnost (CVE-2023-4001) v patchech k zav\u00e1d\u011b\u010di GRUB2 p\u0159ipraven\u00fdch spole\u010dnost\u00ed Red Hat.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/news\/uyazvimost-v-patchah-red-hat-k-zagruzchiku-grub2-pozvolyayushhaya-obojti-proverku-parolya","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\udd47\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432 \u043f\u0430\u0442\u0447\u0430\u0445 Red Hat \u043a \u0437\u0430\u0433\u0440\u0443\u0437\u0447\u0438\u043a\u0443 GRUB2, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043e\u0431\u043e\u0439\u0442\u0438 \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u0443 \u043f\u0430\u0440\u043e\u043b\u044f | 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-2023-4001) \u0432 \u043f\u0430\u0442\u0447\u0430\u0445 \u043a \u0437\u0430\u0433\u0440\u0443\u0437\u0447\u0438\u043a\u0443 GRUB2, \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d\u043d\u044b\u0445 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0435\u0439 Red Hat.","og:url":"https:\/\/prohoster.info\/cs\/blog\/news\/uyazvimost-v-patchah-red-hat-k-zagruzchiku-grub2-pozvolyayushhaya-obojti-proverku-parolya","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":"2024-01-15T15:28:03+00:00","article:modified_time":"2024-01-15T15:28:03+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\/112924","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\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=112924"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/112924\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=112924"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=112924"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=112924"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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Zdroj: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"