{"id":167905,"date":"2026-04-08T11:11:59","date_gmt":"2026-04-08T09:11:59","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/uyazvimost-vo-flatpak-pozvolyayushhaya-vypolnit-kod-vne-izolirovannogo-okruzheniya"},"modified":"2026-04-08T11:11:59","modified_gmt":"2026-04-08T09:11:59","slug":"uyazvimost-vo-flatpak-pozvolyayushhaya-vypolnit-kod-vne-izolirovannogo-okruzheniya","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/news\/uyazvimost-vo-flatpak-pozvolyayushhaya-vypolnit-kod-vne-izolirovannogo-okruzheniya","title":{"rendered":"Zranitelnost ve Flatpaku, kter\u00e1 umo\u017e\u0148uje prov\u00e9st k\u00f3d mimo izolovan\u00e9 prost\u0159ed\u00ed","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Ve vydan\u00e9 zpr\u00e1v\u011b o oprav\u011b syst\u00e9mu samostatn\u00fdch bal\u00edk\u016f Flatpak 1.16.4 a tak\u00e9 ve zku\u0161ebn\u00ed verzi 1.17.4 byla odstran\u011bna zranitelnost (CVE-2026-34078), kter\u00e1 umo\u017e\u0148uje \u0161kodliv\u00e9 nebo kompromitovan\u00e9 aplikaci ve form\u00e1tu flatpak obej\u00edt nastaven\u00fd re\u017eim sandboxov\u00e9 izolace, z\u00edskat p\u0159\u00edstup k soubor\u016fm v z\u00e1kladn\u00edm syst\u00e9mu a vykonat libovoln\u00fd k\u00f3d mimo izolovan\u00fd m\u00f3d. Probl\u00e9m byl klasifikov\u00e1n jako kritick\u00fd (9.3 z 10). <\/p>\n

Zranitelnost se nach\u00e1z\u00ed v D-Bus slu\u017eb\u011b flatpak-portal, kter\u00e1 zaji\u0161\u0165uje spu\u0161t\u011bn\u00ed \u201eport\u00e1l\u016f\u201c, je\u017e se pou\u017e\u00edvaj\u00ed k organizaci p\u0159\u00edstupu k prost\u0159edk\u016fm hlavn\u00edho prost\u0159ed\u00ed z izolovan\u00fdch aplikac\u00ed. Probl\u00e9m je zp\u016fsoben t\u00edm, \u017ee slu\u017eba flatpak-portal umo\u017e\u0148uje aplikaci uv\u00e1d\u011bt v mo\u017enosti sandbox-expose souborov\u00e9 cesty, kter\u00e9 mohou b\u00fdt z d\u016fvodu nedostatku \u0159\u00e1dn\u00fdch kontrol symbolick\u00fdmi odkazy ukazuj\u00edc\u00edmi na libovoln\u00e9 \u010d\u00e1sti souborov\u00e9ho syst\u00e9mu. <\/p>\n

P\u0159ed p\u0159ipojen\u00edm slu\u017eba odhal\u00ed symbolick\u00fd odkaz a p\u0159ipoj\u00ed do sandboxov\u00e9ho prost\u0159ed\u00ed cestu, na kterou ukazuje, co\u017e umo\u017e\u0148uje obej\u00edt izolaci a z\u00edskat p\u0159\u00edstup pro \u010dten\u00ed a z\u00e1pis k soubor\u016fm hostitelsk\u00e9ho prost\u0159ed\u00ed. Aby bylo mo\u017en\u00e9 vykonat sv\u016fj k\u00f3d v syst\u00e9mu, nap\u0159\u00edklad lze p\u0159idat automaticky spou\u0161t\u011bn\u00fd skript, jako je \u201e~\/.bashrc\u201c nebo \u201e~\/.profile\u201c, nebo zm\u011bnit soubor \u201e~\/.ssh\/authorized_keys\u201c s SSH kl\u00ed\u010di. <\/p>\n

Stav odstran\u011bn\u00ed zranitelnosti v distribuc\u00edch lze vyhodnotit na t\u011bchto str\u00e1nk\u00e1ch (pokud nen\u00ed str\u00e1nka dostupn\u00e1, znamen\u00e1 to, \u017ee v\u00fdvoj\u00e1\u0159i distribuce se probl\u00e9mu je\u0161t\u011b neza\u010dali v\u011bnovat): Debian, Ubuntu, SUSE, RHEL, Gentoo, Arch, Fedora. Jako obranou alternativou lze deaktivovat slu\u017ebu flatpak-portal: sudo systemctl --global mask flatpak-portal.service && systemctl --user stop flatpak-portal.service <\/p>\n

Krom\u011b kritick\u00e9 zranitelnosti byla v nov\u00e9 verzi odstran\u011bna je\u0161t\u011b dal\u0161\u00ed t\u0159i bezpe\u010dnostn\u00ed probl\u00e9my: <\/p>\n