Schneider Electric Pelco VideoXpert Privilege Escalations


Vendor: Schneider Electric SE
Product web page: https://www.pelco.com
Affected version: Core Software 1.12.105
                  Media Gateway Software 1.12.26
                  Exports 1.12


Summary: VideoXpert is a video management solution designed for
scalability, fitting the needs surveillance operations of any size.
VideoXpert Ultimate can also aggregate other VideoXpert systems,
tying multiple video management systems into a single interface.

Desc: The application is vulnerable to an elevation of privileges
vulnerability which can be used by a simple user that can change
the executable file with a binary of choice. The vulnerability exist
due to the improper permissions, with the 'F' flag (full) for the
'Users' group, for several binary files. The service is installed
by default to start on system boot with LocalSystem privileges.
Attackers can replace the binary with their rootkit, and on reboot
they get SYSTEM privileges.

VideoXpert services also suffer from an unquoted search path issue
impacting the 'VideoXpert Core' and 'VideoXpert Exports' services
for Windows deployed as part of the VideoXpert Setup bundle. This
could potentially allow an authorized but non-privileged local user
to execute arbitrary code with elevated privileges on the system. A 
successful attempt would require the local user to be able to insert
their code in the system root path undetected by the OS or other security
applications where it could potentially be executed during application
startup or reboot. If successful, the local useras code would execute
with the elevated privileges of the application.

Tested on: Microsoft Windows 7 Professional SP1 (EN)


Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
                            @zeroscience


Advisory ID: ZSL-2017-5418
Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2017-5418.php


05.04.2017

--


C:\Program Files\Pelco\Core>sc qc "VideoXpert Core"
[SC] QueryServiceConfig SUCCESS

SERVICE_NAME: VideoXpert Core
        TYPE               : 10  WIN32_OWN_PROCESS
        START_TYPE         : 2   AUTO_START  (DELAYED)
        ERROR_CONTROL      : 1   NORMAL
        BINARY_PATH_NAME   : C:\Program Files\Pelco\Core\tools\nssm.exe
        LOAD_ORDER_GROUP   :
        TAG                : 0
        DISPLAY_NAME       : VideoXpert Core
        DEPENDENCIES       :
        SERVICE_START_NAME : LocalSystem


C:\>cacls "C:\Program Files\Pelco\Core\tools\nssm.exe"
C:\Program Files\Pelco\Core\tools\nssm.exe NT AUTHORITY\SYSTEM:(ID)F
                                           BUILTIN\Administrators:(ID)F
                                           BUILTIN\Users:(ID)R


C:\ProgramData\Pelco\Core\db\bin>cacls * |findstr "Users:(ID)F"
C:\ProgramData\Pelco\Core\db\bin\libeay32.dll BUILTIN\Users:(ID)F
C:\ProgramData\Pelco\Core\db\bin\mongod.exe BUILTIN\Users:(ID)F
C:\ProgramData\Pelco\Core\db\bin\mongos.exe BUILTIN\Users:(ID)F
C:\ProgramData\Pelco\Core\db\bin\nssm.exe BUILTIN\Users:(ID)F
C:\ProgramData\Pelco\Core\db\bin\ssleay32.dll BUILTIN\Users:(ID)F


C:\>cacls "C:\ProgramData\Pelco\Exports\bin\nssm.exe"
C:\ProgramData\Pelco\Exports\bin\nssm.exe BUILTIN\Users:(ID)F
                                          NT AUTHORITY\SYSTEM:(ID)F
                                          BUILTIN\Administrators:(ID)F


C:\>cacls "C:\ProgramData\Pelco\Gateway\bin\nssm.exe"
C:\ProgramData\Pelco\Gateway\bin\nssm.exe BUILTIN\Users:(ID)F
                                          NT AUTHORITY\SYSTEM:(ID)F
                                          BUILTIN\Administrators:(ID)F



C:\Users\senad>sc qc "VideoXpert Exports"
[SC] QueryServiceConfig SUCCESS

SERVICE_NAME: VideoXpert Exports
        TYPE               : 10  WIN32_OWN_PROCESS
        START_TYPE         : 2   AUTO_START
        ERROR_CONTROL      : 1   NORMAL
        BINARY_PATH_NAME   : C:\ProgramData\Pelco\Exports\bin\nssm.exe
        LOAD_ORDER_GROUP   :
        TAG                : 0
        DISPLAY_NAME       : VideoXpert Exports
        DEPENDENCIES       :
        SERVICE_START_NAME : LocalSystem