Samy kamkar (umcwaningi odumile wezokuphepha owaziwa ngokudala amadivayisi ahlukahlukene wokuhlasela, njenge-keylogger kwishaja yefoni ye-USB) wethule inqubo entsha yokuhlasela ebizwa nge- "NAT slipstreaming".
Ukuhlasela ivumela, lapho kuvulwa ikhasi kusiphequluli, ukusungula ukuxhumana kusuka kuseva yomhlaseli kunoma iyiphi imbobo ye-UDP noma ye-TCP kusistimu yomsebenzisi ngemuva kwesihumushi sekheli. I-Attack Toolkit ishicilelwe ku-GitHub.
Indlela uthembele ekukhohliseni indlela yokulandela umkhondo ye-ALG (Application Level Gateways) ekhelini labahumushi noma kwizicishamlilo, ezisetshenziselwa ukuhlela ukudluliswa kwe-NAT kwamaphrothokholi asebenzisa amachweba amaningi wenethiwekhi (eyodwa yedatha neyokulawula), njenge-SIP. H323, IRC DCC ne-FTP.
Lokhu kuhlasela kusebenza kubasebenzisi abaxhumeka kunethiwekhi kusetshenziswa amakheli angaphakathi avela kububanzi be-intranet (192.168.xx, 10.xxx) futhi ivumela noma iyiphi idatha ukuthi ithunyelwe kunoma iyiphi imbobo (azikho izihloko ze-HTTP).
Ukuhlasela, kwanele ukuthi isisulu sisebenzise ikhodi yeJavaScript elungiselelwe ngumhlaseliIsibonelo, ngokuvula ikhasi kuwebhusayithi yomhlaseli noma ngokubuka isikhangiso esinonya kuwebhusayithi esemthethweni.
Esigabeni sokuqala, umhlaseli uthola ulwazi mayelana nekheli langaphakathi lomsebenzisi, Lokhu kunganqunywa yi-WebRTC noma, uma i-WebRTC ikhutshaziwe, ngokuhlaselwa ngamandla ngesihluku isikhathi sokuphendula lapho ucela isithombe esifihliwe (sabaphathi abakhona, umzamo wokucela isithombe ushesha kakhulu kunalezo ezingekho ngenxa yokuphelelwa yisikhathi ngaphambi kokubuyisa i-TCP Impendulo ye-RST).
Esigabeni sesibili, ikhodi yeJavaScript wabulawa esipheqululini sesisulu ikhiqiza isicelo esikhulu se-HTTP POST (engalingani ephaketheni) kuseva yomhlaseli esebenzisa inombolo ye-port yenethiwekhi engajwayelekile ukuqala ukushuna kwamapharamitha wokuhlukaniswa kwe-TCP nosayizi we-MTU kusitaki se-TCP sesisulu.
Ukuphendula, iseva yomhlaseli ibuyisa iphakethe le-TCP ngenketho ye-MSS (Ubukhulu besayizi yengxenye), enquma usayizi omkhulu wepakethe etholiwe. Endabeni ye-UDP, ukukhwabanisa kuyafana, kepha kuncike ekuthumeleni isicelo esikhulu seWebRTC TURN ukuqala ukuhlukaniswa kwezinga le-IP.
«I-NAT Slipstreaming ixhaphaza isiphequluli somsebenzisi ngokubambisana ne-Application Level Gateway (ALG) yokulandelela indlela yokuxhuma eyakhelwe ku-NAT, ama-routers, nama-firewalls ngokufaka iketanga nge-IP yangaphakathi ngokuhlasela kwesikhathi noma nge-WebRTC, ukutholakala kokuqhekeka kwe-IP eyi-automated ne-MTU, TCP ukuphucwa usayizi wamaphakethe, ukusetshenziswa kabi kokuqinisekiswa kwe-TURN, ukulawulwa okuqondile kwemikhawulo yamaphakethe nokudideka kweprothokholi kusuka ekuhlukunyezweni kwesiphequluli, "kusho uKamkar ekuhlaziyeni.
Umqondo oyinhloko ngukuthi lokho, ngokwazi amapharamitha wokuhlukaniswa, angakwazi thumela isicelo esikhulu se-HTTP, umugqa wazo uzowela kwiphakethe lesibili. Ngasikhathi sinye, umugqa ongena ephaketheni lesibili uyakhethwa ukuze ungaqukethe izihloko ze-HTTP futhi unqunywe kudatha ehambelana ngokuphelele nenye iphrothokholi lapho ukuwela kwe-NAT kusekelwa khona.
Esigabeni sesithathu, kusetshenziswa ukukhohlisa okungenhla, ikhodi yeJavaScript yakha futhi ithumele isicelo esikhethwe ngokukhethekile se-HTTP (noma i-TURN ye-UDP) ethekwini le-TCP 5060 yeseva yomhlaseli, okuthi, ngemuva kokuhlukaniswa, kuhlukaniswe ngamaphakethe amabili: a iphakethe elinezihloko ze-HTTP nengxenye yedatha kanye nephakethe le-SIP elivumelekile ne-IP yangaphakathi yesisulu.
Uhlelo lokulandelela ukuxhumana kusitaki senethiwekhi izothatha leli phakethe njengeliqala kweseshini ye-SIP futhi kuzovumela ukudluliswa kwepakethe kwanoma iyiphi imbobo ekhethwe umhlaseli, kucatshangwa ukuthi leli chweba lisetshenziselwa ukudluliswa kwedatha.
Ukuhlasela kungenziwa kungakhathalekile ukuthi isiphequluli sisetshenzisiwe. Ukuxazulula inkinga, abathuthukisi beMozilla baphakamise ukuvimba amandla okuthumela izicelo ze-HTTP kumanethiwekhi wenethiwekhi ama-5060 no-5061 ahlobene ne-protocol ye-SIP.
Abathuthukisi bezinjini zeChromium, Blink neWebKit nabo bahlose ukusebenzisa isilinganiso sokuvikela esifanayo.
Umthombo: https://samy.pl