CVE Candidate - Privilege Escalation in Compusource Real Time Home Banking

# Exploit Title: CompuSource Systems - Real Time Home Banking - Local Privilege Escalation/Arbitrary Code Execution

# Date: 2/25/16

# Exploit Author: singularitysec@gmail.com

# Vendor Homepage: https://www.css4cu.com

# Version: CompuSource Systems - Real Time Home Banking

# Tested on: Windows 7

# CVE : TBD

Note: Windows Server 2003/2008/2012  *may* be vulnerable, depending on system configuration.

This vulnerability has been reference checked against multiple installs. This configuration was identical across all systems tested.
Executables/Services:
%SystemRoot%/css50/csdir/RealTimeHomeBankingSvc.exe
HomeBankingService
Attack Detail:

The application installs with LOCAL SYSTEM service credentials in the directory %SystemRoot%/css50/csdir

The executables that are installed, by default, allow AUTHENTICATED USERS to modify, replace or alter the file. This would allow an attacker to inject their code or replace the executable and have it run in the context of the system.


This would allow complete compromise of a machine on which it was installed, giving the process LOCAL SYSTEM access to the machine in question. An attacker can replace the file or append code to the executable, reboot the system or restart the service and it would then  compromise the machine. As LOCAL SYSTEM is the highest privilege level on a machine, this allows total control and access to all parts of the system.

Remediation:
Remove the modify/write permissions on the executables to allow only privileged users to alter the files.
Apply vendor patch when distributed.
Vulnerability Discovered: 2/25/16
Vendor Notified: 2/25/16
                                                                                         
Website: www.information-paradox.net
This vulnerability was discovered by singularitysec@gmail.com. Please credit the author in all references to this exploit.