Kevin Backhouse (muongorori wezvekuchengetedza) yakagovaniswa mazuva mashoma apfuura paGitHub blog iyo noti iyo ndakasangana nekanganiso mu polkit sevhisi inosangana ne systemd (yakajairika Linux system uye sevhisi manejimendi chikamu), icho chine makore manomwe ekukuvadzwa icho kubvumidzwa kuita kukwidziridzwa kweropafadzo iyo yanga ichihwanda mukuparadzirwa kwakasiyana siyana kweLinux uye yaive yakanamirwa svondo rapfuura mukuburitswa kwakabatana.
Polkit ibhuku rekushandisa-chikamu chekutsanangura uye kugadzirisa mutemo iyo inobvumira iyo maitiro asina rukudzo Taura nemaitiro eropafadzo, inoisa nekumisikidza pane akasiyana ekugoverwa kweLinux. Iyo kushushikana kwakaunzwa mushanduro 0.113 makore manomwe apfuura (ita bfa5036) uye yakagadziriswa muna Chikumi 3 mushure mekuburitswa kwayo kuchangobva kuitwa nemuongorori wezvekuchengetedza Kevin Backhouse.
Senhengo yeGitHub Security Lab, basa rangu nderekubatsira kusimudzira kuchengetedzeka kweyakavhurika sosi software nekutsvaga uye nekuzivisa kusagadzikana. Mavhiki mashoma apfuura, ini ndakawana ropafadzo yekukwira kunetsekana mupolkit. Yakarongedzwa kushomeka kuburitswa nevachengeti ve polkit uye timu yekuchengetedza yeRed Hat. Yakaitwa pachena, gadziriso yakaburitswa munaJune 3, 2021 uye yakapihwa CVE-2021-3560
"Yese Linux system iyo inoshandisa iyo isinganetsi vhezheni yepolkit inogona kuratidzirwa pakurwiswa kunoshandisa iyo CVE-2021-3560 kukanganisa," anodaro Backhouse. inoti kukanganisa kwacho kunoshamisa kushandisa, sezvo ichingoda iwo mashoma mirairo uchishandisa yakajairika maturusi maturusi senge bash, kuuraya, uye dbus-send.
"Kunetseka kunokonzerwa nekutanga dbus-send command, asi kuuraya iyo polkit ichiri kugadzirisa chikumbiro," Backhouse akatsanangura.
back-house akatumira vhidhiyo PoC yekurwiswa kunoshandisa uku kushushikana kuchiratidza kuti zviri nyore kuita.
“Kunetseka kunopa mukana mushandisi asina pekugara kuwana ganda remudzi pachirongwa ichi. Zviri nyore kushandisa nezvimwe zvakajairwa-mutsara maturusi, sezvaungaona mune ino pfupi vhidhiyo, 'yakanyora nyanzvi mune blog blog.
Kana uchiuraya dbus-send (rairo yekutaurirana pakati pezvakaitwa), pakati pechikumbiro chechokwadi chinokonzera kukanganisa Izvo zvinouya kubva polkit ichikumbira iyo UID yekubatanidza iyo isisipo (nekuti iko kubatana kwakadonhedzwa).
"Chokwadi, polkit inobata chikanganiso nenzira isingafadzi: pachinzvimbo chekuramba chikumbiro, chinoibata sekunge yakabva mukuita neUID 0," Backhouse anotsanangura. "Mune mamwe mazwi, iwe unobva wabvumidza chikumbiro nekuti iwe unofunga kuti chikumbiro chinobva mukugadzirisa midzi."
Izvi hazviitike nguva dzese, nekuti mubvunzo weUID wepolkit kune dbus-daemon inoitika kakawanda munzira dzakasiyana dzekodhi. Kazhinji idzo kodhi nzira dzinobata iko kukanganisa nenzira kwayo, Backhouse akadaro, asi kodhi nzira iri panjodzi, uye kana iyo disconnect ikaitika kana iyo kodhi nzira iri kushanda, ipapo kukwidziridzwa kweropafadzo kunoitika. Izvo zvese inyaya yenguva, iyo inosiyana munzira dzisingafungidzike nekuti maitiro mazhinji anobatanidzwa.
Uyewo, muongorori akaburitsa tafura inotevera iyo iine runyorwa rwekuparadzaniswa parizvino kunetseka
| KUPARADZWA | ZVINOTAMBUDZIKA? |
|---|---|
| rhel 7 | Aihwa |
| rhel 8 | hongu |
| Fedora 20 (kana pakutanga) | Aihwa |
| Fedora 21 (kana kuti gare gare) | hongu |
| Debian 10 ("bhasi") | Aihwa |
| Debian kuyedza | hongu |
| Ubuntu 18.04 | Aihwa |
| Ubuntu 20.04 | hongu |
Kugoverwa kweLinux ine polkit vhezheni 0.113 kana gare gare yakaiswa, senge Debian (isina kugadzikana bazi), RHEL 8, Fedora 21 uye yakakwira, uye Ubuntu 20.04, zvinokanganiswa.
Hunhu hwepakati hwebug, Backhouse inofungidzira, ndicho chikonzero chakaenda chisina kuzivikanwa kwemakore manomwe.
"CVE-2021-3560 inobvumira murwi wemunharaunda asina mukana kuti awane mukana," akadaro Backhouse. "Zviri nyore kwazvo uye zvinokurumidza kushandisa, saka zvakakosha kuti iwe uvandudze kuiswa kwako kweLinux nekukurumidza sezvazvinogona."
Finalmente Kana iwe uchifarira kuziva zvakawanda nezvazvo, unogona kutarisa ruzivo Mune inotevera chinongedzo.