Uma exhashazwa, lawa maphutha angavumela abahlaseli ukuthi bathole ukufinyelela okungagunyaziwe kulwazi olubucayi noma ngokuvamile babangele izinkinga.
Ulwazi lusanda kukhishwa ukuthi kutholwe ukuba sengozini kwe-Linux kernel enamaphuzu we-CVSS angu-10 kuseva ye-SMB, enikeza umsebenzisi ongagunyaziwe ikhono lokukhipha ikhodi ekude.
Isiphazamisi esitholiwe sivumela abahlaseli besilawuli kude ukuthi basebenzise ikhodi engafanele ekufakweni okuthintekile. Ukuqinisekisa akudingekile ukuze kusetshenziswe lobu bungozi, kodwa amasistimu ane-ksmbd anikwe amandla kuphela asengozini.
Iphutha elithile likhona ekucubungulweni kwemiyalelo ye-SMB2_TREE_DISCONNECT. Inkinga ibangelwa ukungaqinisekisi ukuthi into ikhona ngaphambi kokwenza imisebenzi kuleyo nto. Umhlaseli angasebenzisa lobu bungozi ukuze akhiphe ikhodi kumongo we-kernel.
IMINININGWANE YOBUNGOZI
Lokhu kuba sengozini kuvumela abahlaseli berimothi ukuthi basebenzise ikhodi engafanele ekufakweni okuthintekile kwe-Linux Kernel. Ukuqinisekisa akudingekile ukuze kusetshenziswe lobu bungozi, kodwa amasistimu ane-ksmbd anikwe amandla kuphela asengozini.Iphutha elithile likhona phakathi kokucutshungulwa kwemiyalelo ye-SMB2_TREE_DISCONNECT. Inkinga ibangelwa ukuntuleka kokuqinisekiswa kokuba khona kwento ngaphambi kokwenza imisebenzi entweni. Umhlaseli angasebenzisa lobu bungozi ukuze akhiphe ikhodi kumongo we-kernel.
Kushiwo ukuthi kuye ngohlobo lwesicelo se-SMB, intambo entsha ngayinye inganquma ukudlulisa imiyalo esikhaleni somsebenzisi (ksmbd.mountd); okwamanje, imiyalo ye-DCE/RPC ikhonjwa ukuthi isingathwe yisikhala somsebenzisi. Ukuze kusetshenziswe kangcono i-Linux kernel, kwanqunywa ukuphatha imiyalo njengezinto zomsebenzi futhi isetshenziswe kuzibambi zentambo ze-ksmbd -io kworker.
Lokhu kuvumela abaphathi ukuthi baphindaphinde i-multiplex ngoba i-kernel inakekela ukuqala izintambo ezengeziwe zezisebenzi uma umthwalo ukhuphuka futhi okuphambene nalokho, uma umthwalo wehla, ibulala izintambo zesisebenzi ezengeziwe.
Uma i-daemon yeseva iqala, iqala intambo yemfoloko (ksmbd/igama lesixhumi esibonakalayo) ngesikhathi sokuqalisa futhi ivula imbobo ezinikele engu-445 ukuze ilalele izicelo ze-SMB. Ngaso sonke isikhathi lapho amaklayenti amasha enza isicelo, intambo yeforka yamukela uxhumano lweklayenti futhi yakha uchungechunge olusha lwesiteshi sokuxhumana esizinikele phakathi kweklayenti neseva. Lokhu kuvumela izicelo ze-SMB (imiyalo) ezivela kumakhasimende ukuthi zicutshungulwe ngokuhambisana futhi kuvumela amaklayenti amasha ukuthi asungule ukuxhumana okusha.
I-ksmbd iphakamise amafulegi abomvu phakathi kwabanye abasebenzisi abaxoxe ngokuhlangana kwabo ngonyaka odlule. I-SerNet, inkampani yamakhompiyutha yaseJalimane enikeza inguqulo yayo ye-Samba, yathi eposini lebhulogi i-ksmbd yayinhle, kodwa ibonakala ingavuthiwe. Ukwengeza, ithimba le-SerNet's Samba+ lishilo eposini lebhulogi ukuthi inani lokwengeza iseva ye-SMB esikhaleni se-kernel lingase lingayifanele ingozi "yokucindezela okokugcina kokusebenza ezintweni ezitholakalayo."
Ngenhlanhla, uma ungasebenzisi imojuli "yokuhlola" ye-ksmbd yakwaSamsung, njengoba kuchazwe umcwaningi wezokuphepha u-Shir Tamari ku-Twitter, futhi ugcine i-Samba, uphephe ngokuphelele. “i-ksmbd yintsha; abasebenzisi abaningi basasebenzisa i-Samba futhi abathinteki. Empeleni, uma ungasebenzisi amaseva e-SMB nge-ksmbd, jabulela impelasonto yakho,” kusho uTamari kuTwitter.
Ngokusho kweZero-Day Initiative, eyembule ukuba sengozini kwe-ksmbd, iphutha lokusebenzisa ngemva kwamahhala likhona ekucubungulweni kwemiyalelo ye-SMB2_TREE_DISCONNECT. Ngokusho kwe-ZDI, inkinga ibangelwa ukuthi i-ksmbd ingaqinisekisa ubukhona bezinto ngaphambi kokwenza imisebenzi kuzo.
Kulabo abasebenzisa i-ksmbd, kune-workaround ngaphandle kokushintshela ku-Samba: thuthukela ku-Linux kernel version 5.15.61, ekhishwe ngo-August, noma kamuva. Lesi sibuyekezo se-kernel siphinde silungise ezinye izinkinga ezimbalwa ku-ksmbd: ukuphuma kwemingcele kufundwe kwe-SMB2_TREE_CONNECT, okuthi ngokwenothi lesichibi kungavumela izicelo ezingavumelekile ukuthi zingathumeli imilayezo, kanye nokuvuza kwememori ku-smb2_handle_negotiate okubangela mahhala okungalungile. inkumbulo.
ekugcineni uma ukhona unentshisekelo yokwazi okwengeziwe ngayo, ungabheka imininingwane Kulesi sixhumanisi esilandelayo.