{"id":172666,"date":"2026-05-19T00:24:49","date_gmt":"2026-05-18T22:24:49","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/v-exim-4-99-3-ustranena-uyazvimost-pozvolyayushhaya-udalyonnoe-vypolnenie-koda-pri-ispolzovanii-gnutls"},"modified":"2026-05-19T00:24:49","modified_gmt":"2026-05-18T22:24:49","slug":"v-exim-4-99-3-ustranena-uyazvimost-pozvolyayushhaya-udalyonnoe-vypolnenie-koda-pri-ispolzovanii-gnutls","status":"publish","type":"post","link":"https:\/\/prohoster.info\/hr\/blog\/news\/v-exim-4-99-3-ustranena-uyazvimost-pozvolyayushhaya-udalyonnoe-vypolnenie-koda-pri-ispolzovanii-gnutls","title":{"rendered":"U Exim 4.99.3 ispravljena je ranjivost koja omogu\u0107ava daljinsko izvr\u0161avanje koda prilikom kori\u0161tenja GnuTLS.","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Razvija\u010di po\u0161tanskog servera Exim izbacili su ispravku Exim 4.99.3<\/strong>, koja otklanja ranjivost u nekim konfiguracijama po\u0161tanskog agenta. Problem nosi unutarnji identifikator EXIM-Security-2026-05-01.1<\/strong>; u slu\u017ebenom obavje\u0161tenju tako\u0111e se navodi kao CVE-TBD<\/strong>.<\/p>\n

Ranjivost spada u klasu Remote Use-After-Free<\/strong> i manifestuje se prilikom analize tijela poruke BDAT<\/strong> prilikom rada TLS preko GnuTLS<\/strong>. BDAT se koristi u SMTP ekstenziji CHUNKING<\/strong> za prenos tijela poruke u blokovima. Prema opisu Exim-a, gre\u0161ka mo\u017ee nastati kada klijent tokom prenosa BDAT po\u0161alje TLS obavijest close_notify pre zavr\u0161etka prenosa tijela, a zatim doda dodatni bajt unutar iste TCP veze.<\/p>\n

U takvoj sekvenci Exim mo\u017ee zapisivati podatke u memorijski bafer koji je ve\u0107 oslobo\u0111en na kraju TLS sesije. To dovodi do o\u0161te\u0107enja hrpe i potencijalno se mo\u017ee iskoristiti za izvr\u0161enje koda. U obavje\u0161tenju se nagla\u0161ava da napada\u010du dovoljno da ima mogu\u0107nost uspostaviti TLS vezu i koristiti SMTP ekstenziju CHUNKING \/ BDAT<\/strong>.<\/p>\n

Problem se ti\u010de Exim 4.97, 4.98, 4.99, 4.99.1 i 4.99.2<\/strong>, ali samo verzije koje su sastavljene s podr\u0161kom GnuTLS<\/strong>. U slu\u017ebenoj dokumentaciji to je formulirano kao konfiguracije s USE_GNUTLS=yes; verzije koje koriste OpenSSL<\/strong> ili druge TLS biblioteke, nisu pogo\u0111ene ovom ranjivo\u0161\u0107u. Tako\u0111e, u obavje\u0161tenju Exim se posebno isti\u010de da su ranjive konfiguracije u kojima je deklarisan STARTTLS<\/strong> i CHUNKING<\/strong>.<\/p>\n

Ispravka je uklju\u010dena u Exim 4.99.3<\/strong>. Prema opisu programera, zakrpa garantuje \u010di\u0161\u0107enje steka obrade ulaza prilikom primanja TLS close_notify tokom aktivnog prenosa BDAT, \u010dime se spre\u010dava dalje kori\u0161\u0107enje zastarjelih pokaziva\u010da. Drugog poznatog na\u010dina da se problem potpuno re\u0161i, osim a\u017euriranja, u preporukama nema.<\/p>\n

Razvija\u010di Exim-a su primili prijavu za gre\u0161ku 1. maja 2026. godine<\/strong> od Federica Kirschbauma iz XBOW Security<\/strong>. Nakon pregleda izve\u0161taja, ispravka se pripremala u zatvorenim repozitorijima, 7. maja je o problemu obave\u0161teno distribuirane verzije putem zatvorenog mailing lista, 10. maja im je pru\u017een ograni\u010den pristup ispravkama, a 12. maja 2026. godine<\/strong> objavljene su preporuke i sama ispravka.<\/p>\n

Administratorima po\u0161tanskih servera se preporu\u010duje da provere koja verzija Exim-a i TLS backend se koristi. server<\/a> radi na Exim od 4.97 do 4.99.2 uklju\u010divo, sastavljen s GnuTLS i ogla\u0161ava STARTTLS uz CHUNKING, projekt Exim preporu\u010duje \u0161to br\u017ei prijelaz na Exim 4.99.3<\/strong> ili noviju verziju. Ispravljeni izvorni tekstovi dostupni su u grani exim-4.99+fixes i oznaci exim-4.99.3, kao i u obliku tarball arhiva na uobi\u010dajenim mjestima za preuzimanje Exima.<\/p>\n

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

\u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 Exim \u0432\u044b\u043f\u0443\u0441\u0442\u0438\u043b\u0438 \u043a\u043e\u0440\u0440\u0435\u043a\u0442\u0438\u0440\u0443\u044e\u0449\u0438\u0439 \u0440\u0435\u043b\u0438\u0437 Exim 4.99.3, \u0443\u0441\u0442\u0440\u0430\u043d\u044f\u044e\u0449\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432 \u043d\u0435\u043a\u043e\u0442\u043e\u0440\u044b\u0445 \u043a\u043e\u043d\u0444\u0438\u0433\u0443\u0440\u0430\u0446\u0438\u044f\u0445 \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0430\u0433\u0435\u043d\u0442\u0430. \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043f\u0440\u043e\u0445\u043e\u0434\u0438\u0442 \u043f\u043e\u0434 \u0432\u043d\u0443\u0442\u0440\u0435\u043d\u043d\u0438\u043c \u0438\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u043e\u043c EXIM-Security-2026-05-01.1; \u0432 \u043e\u0444\u0438\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u043c \u0443\u0432\u0435\u0434\u043e\u043c\u043b\u0435\u043d\u0438\u0438 \u0442\u0430\u043a\u0436\u0435 \u0444\u0438\u0433\u0443\u0440\u0438\u0440\u0443\u0435\u0442 \u043a\u0430\u043a CVE-TBD. \u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043e\u0442\u043d\u043e\u0441\u0438\u0442\u0441\u044f \u043a \u043a\u043b\u0430\u0441\u0441\u0443 Remote Use-After-Free \u0438 \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u043f\u0440\u0438 \u0440\u0430\u0437\u0431\u043e\u0440\u0435 \u0442\u0435\u043b\u0430 \u0441\u043e\u043e\u0431\u0449\u0435\u043d\u0438\u044f BDAT \u043f\u0440\u0438 \u0440\u0430\u0431\u043e\u0442\u0435 TLS \u0447\u0435\u0440\u0435\u0437 GnuTLS. BDAT \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u0435\u0442\u0441\u044f \u0432 SMTP-\u0440\u0430\u0441\u0448\u0438\u0440\u0435\u043d\u0438\u0438 CHUNKING \u0434\u043b\u044f \u043f\u0435\u0440\u0435\u0434\u0430\u0447\u0438 \u0442\u0435\u043b\u0430 […]<\/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-172666","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\udd47U Exim 4.99.3 uklonjena je ranjivost koja omogu\u0107uje daljinsko izvo\u0111enje koda pri kori\u0161tenju GnuTLS | ProHoster","description":"Programeri po\u0161tanskog poslu\u017eitelja Exim objavili su ispravak za Exim 4.99.3, koji otklanja sigurnosnu ranjivost u nekim konfiguracijama po\u0161tanskog agenta.","canonical_url":"https:\/\/prohoster.info\/hr\/blog\/news\/v-exim-4-99-3-ustranena-uyazvimost-pozvolyayushhaya-udalyonnoe-vypolnenie-koda-pri-ispolzovanii-gnutls","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\udd47\u0412 Exim 4.99.3 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e\u0435 \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u0435 \u043a\u043e\u0434\u0430 \u043f\u0440\u0438 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0438 GnuTLS | ProHoster","og:description":"\u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 Exim \u0432\u044b\u043f\u0443\u0441\u0442\u0438\u043b\u0438 \u043a\u043e\u0440\u0440\u0435\u043a\u0442\u0438\u0440\u0443\u044e\u0449\u0438\u0439 \u0440\u0435\u043b\u0438\u0437 Exim 4.99.3, \u0443\u0441\u0442\u0440\u0430\u043d\u044f\u044e\u0449\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0432 \u043d\u0435\u043a\u043e\u0442\u043e\u0440\u044b\u0445 \u043a\u043e\u043d\u0444\u0438\u0433\u0443\u0440\u0430\u0446\u0438\u044f\u0445 \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0430\u0433\u0435\u043d\u0442\u0430.","og:url":"https:\/\/prohoster.info\/hr\/blog\/news\/v-exim-4-99-3-ustranena-uyazvimost-pozvolyayushhaya-udalyonnoe-vypolnenie-koda-pri-ispolzovanii-gnutls","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":"2026-05-18T22:24:49+00:00","article:modified_time":"2026-05-18T22:24:49+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\/172666","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=172666"}],"version-history":[{"count":1,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/posts\/172666\/revisions"}],"predecessor-version":[{"id":173168,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/posts\/172666\/revisions\/173168"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/media?parent=172666"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/categories?post=172666"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/hr\/wp-json\/wp\/v2\/tags?post=172666"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}