{"id":100086,"date":"2021-05-04T22:22:55","date_gmt":"2021-05-04T20:22:55","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/obnovlenie-exim-4-94-2-s-ustraneniem-10-udalyonno-ekspluatiruemyh-uyazvimostej"},"modified":"2021-05-04T22:22:55","modified_gmt":"2021-05-04T20:22:55","slug":"obnovlenie-exim-4-94-2-s-ustraneniem-10-udalyonno-ekspluatiruemyh-uyazvimostej","status":"publish","type":"post","link":"https:\/\/prohoster.info\/hu\/blog\/news\/obnovlenie-exim-4-94-2-s-ustraneniem-10-udalyonno-ekspluatiruemyh-uyazvimostej","title":{"rendered":"Az Exim 4.94.2 friss\u00edt\u00e9se, amely 10 t\u00e1volr\u00f3l kihaszn\u00e1lhat\u00f3 sebezhet\u0151s\u00e9get jav\u00edt","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Megjelent az Exim 4.94.2 levelez\u0151szerver kiad\u00e1sa, amely 21 sebezhet\u0151s\u00e9g (CVE-2020-28007-CVE-2020-28026, CVE-2021-27216) jav\u00edt\u00e1s\u00e1t tartalmazza, amelyeket a Qualys c\u00e9g az 21Nails k\u00f3dn\u00e9v alatt azonos\u00edtott. 10 probl\u00e9ma t\u00e1volr\u00f3l kihaszn\u00e1lhat\u00f3 (t\u00f6bbek k\u00f6z\u00f6tt root jogosults\u00e1g\u00fa k\u00f3d v\u00e9grehajt\u00e1s\u00e1ra) az SMTP-parancsok manipul\u00e1l\u00e1s\u00e1val a szerverrel val\u00f3 interakci\u00f3 sor\u00e1n. <\/p>\n

A probl\u00e9m\u00e1k minden Exim verzi\u00f3t \u00e9rintenek, amelyek t\u00f6rt\u00e9nete 2004 \u00f3ta nyomon k\u00f6vethet\u0151 a Git-ben. 4 helyi sebezhet\u0151s\u00e9g \u00e9s 3 t\u00e1voli probl\u00e9ma eset\u00e9n m\u0171k\u00f6d\u0151 exploit protot\u00edpusok k\u00e9sz\u00fcltek. A helyi sebezhet\u0151s\u00e9gekhez (CVE-2020-28007, CVE-2020-28008, CVE-2020-28015, CVE-2020-28012) k\u00e9sz\u00edtett exploitok r\u00e9v\u00e9n a felhaszn\u00e1l\u00f3k jogosults\u00e1gait a root szintj\u00e9re emelhetik. K\u00e9t t\u00e1voli probl\u00e9ma (CVE-2020-28020, CVE-2020-28018) lehet\u0151v\u00e9 teszi a felhaszn\u00e1l\u00f3 exim jogosults\u00e1gainak kihaszn\u00e1l\u00e1s\u00e1t hiteles\u00edt\u00e9s n\u00e9lk\u00fcl (ezut\u00e1n root hozz\u00e1f\u00e9r\u00e9s szerezhet\u0151 meg helyi sebezhet\u0151s\u00e9gek kihaszn\u00e1l\u00e1s\u00e1val). <\/p>\n

A CVE-2020-28021 vulnerability allows for immediate remote code execution with root privileges but requires authenticated access (the user must establish an authenticated session, after which they can exploit the vulnerability through manipulation of the AUTH parameter in the MAIL FROM command). The issue arises because the attacker can achieve string substitution in the spool file header due to the unescaped writing of the authenticated_sender value (for example, by sending the command \"MAIL FROM: AUTH=Raven+0AReyes\"). <\/p>\n

Additionally, it is noted that another remote vulnerability, CVE-2020-28017, can be exploited for code execution with the 'exim' user privileges without authentication but requires more than 25 GB of memory. For the other 13 vulnerabilities, exploits could potentially be prepared, but work in this direction has not yet been conducted. <\/p>\n

Az Exim fejleszt\u0151i m\u00e1r tavaly okt\u00f3berben \u00e9rtes\u00fcltek a probl\u00e9m\u00e1kr\u00f3l, \u00e9s t\u00f6bb mint 6 h\u00f3napot t\u00f6lt\u00f6ttek a jav\u00edt\u00e1sok kidolgoz\u00e1s\u00e1val. Minden adminisztr\u00e1tor sz\u00e1m\u00e1ra s\u00fcrg\u0151sen javasolt az Exim friss\u00edt\u00e9se a levelez\u0151szervereken. szervereken<\/a> a 4.94.2 verzi\u00f3ig. Minden Exim verzi\u00f3, amely a 4.94.2 kiad\u00e1s el\u0151tt k\u00e9sz\u00fclt, elavultnak van nyilv\u00e1n\u00edtva. Az \u00faj verzi\u00f3 k\u00f6zz\u00e9t\u00e9tel\u00e9t a disztrib\u00faci\u00f3kkal \u00f6sszhangban hajtott\u00e1k v\u00e9gre, amelyek egyszerre adt\u00e1k ki a csomagfriss\u00edt\u00e9seket: Ubuntu, Arch Linux, FreeBSD, Debian, SUSE \u00e9s Fedora. A RHEL \u00e9s a CentOS nem \u00e9rintett, mivel az Exim nem szerepel a csomagjaik hivatalos t\u00e1rol\u00f3j\u00e1ban (EPEL-ben a friss\u00edt\u00e9s m\u00e9g nem \u00e1ll rendelkez\u00e9sre). <\/p>\n

T\u00e1voli sebezhet\u0151s\u00e9gek: <\/p>\n