CVE-2025-66269: UPSilon 2000 Unquoted Service Paths Allow Privilege Escalation

Overview

CVE-2025-66269 is a vulnerability affecting UPSilon 2000, a power management software suite. The vulnerability stems from unquoted service paths in the configuration of the RupsMon and USBMate services. These services, which run with SYSTEM privileges, are susceptible to a local privilege escalation attack.

Technical Details

The issue arises because the paths to the RupsMon and USBMate service executables within the Windows Registry are not enclosed in quotation marks. When Windows starts a service with an unquoted path, it attempts to execute each space-separated part of the path as a program. For example, if the path is C:\Program Files\UPSilon 2000\RupsMon.exe, Windows will attempt to execute C:\Program, then C:\Program Files, and so on.

A local attacker with write permissions to directories preceding the actual service executable’s location can exploit this. By placing a malicious executable named “Program.exe” in the C:\ directory, “Files.exe” in the C:\Program directory, or similar, the attacker can intercept the service startup process and execute their code with SYSTEM privileges.

Affected Services:

• RupsMon
• USBMate

CVSS Analysis

Currently, there is no CVSS score available for CVE-2025-66269. However, given the nature of the vulnerability (local privilege escalation), the impact is potentially significant. A successful exploit allows a local attacker to gain full control of the system.

Possible Impact

A successful exploit of CVE-2025-66269 could have severe consequences:

• Full System Compromise: The attacker gains SYSTEM privileges, allowing them to perform any action on the affected system.
• Data Theft: Sensitive data can be accessed and exfiltrated.
• Malware Installation: The attacker can install malware, backdoors, or other malicious software.
• System Disruption: The attacker can disrupt system operations, leading to denial of service.

Mitigation or Patch Steps

The primary mitigation strategy involves ensuring that the service paths for RupsMon and USBMate are enclosed in quotation marks in the Windows Registry.

1. Apply the Official Patch (If Available): Check the vendor’s website (https://www.megatec.com.tw/software-download/) for an official patch or updated version of UPSilon 2000 that addresses this vulnerability. Apply the patch according to the vendor’s instructions.
2. Manual Remediation (If Patch Unavailable): If a patch is not available, manually modify the Windows Registry:
   • Open the Registry Editor (regedit).
   • Navigate to the registry keys for the RupsMon and USBMate services (typically found under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\).
   • Locate the ImagePath value for each service.
   • Add quotation marks around the entire path to the executable. For example, change C:\Program Files\UPSilon 2000\RupsMon.exe to "C:\Program Files\UPSilon 2000\RupsMon.exe".
   • Restart the services or the entire system for the changes to take effect.
3. Least Privilege Principle: Even with the mitigation, adhere to the principle of least privilege. Restrict user accounts to only the permissions necessary to perform their tasks.

References

• Megatec Software Download