CVE-2019-25275: BartVPN Privilege Escalation Vulnerability

CVE-2019-25275 Overview

BartVPN 1.2.2 contains an unquoted service path vulnerability in the BartVPNService that allows local attackers to potentially execute arbitrary code with elevated system privileges. This vulnerability arises from improper handling of the service executable path, enabling attackers to hijack the service's execution context by placing malicious executables in specific file system locations.

Critical Impact

Local attackers with limited privileges can escalate to SYSTEM-level access by exploiting the unquoted service path, potentially leading to full system compromise.

Affected Products

• BartVPN 1.2.2
• BartVPNService component

Discovery Timeline

• 2026-02-05 - CVE CVE-2019-25275 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2019-25275

Vulnerability Analysis

This vulnerability falls under CWE-428 (Unquoted Search Path or Element), a common misconfiguration in Windows services where executable paths containing spaces are not properly enclosed in quotation marks. When Windows attempts to start a service with an unquoted path containing spaces, it sequentially attempts to execute binaries at each space-delimited path segment.

For example, if the BartVPNService is configured with a path like C:\Program Files\BartVPN\service.exe, Windows will attempt to execute in the following order:

1. C:\Program.exe
2. C:\Program Files\BartVPN\service.exe

This behavior creates an opportunity for privilege escalation since Windows services typically run under the SYSTEM account. An attacker with write access to C:\ or C:\Program Files\ can place a malicious executable named Program.exe that will be executed with elevated privileges when the service starts or restarts.

Root Cause

The root cause of this vulnerability is the failure to enclose the service binary path in quotation marks during the service registration process. When the BartVPNService was registered in the Windows Service Control Manager (SCM), the ImagePath registry value was set without proper quoting, leaving the path vulnerable to exploitation. This is a common oversight during software installation routines that do not properly sanitize or quote file paths containing spaces.

Attack Vector

This is a local privilege escalation attack requiring an authenticated user with the ability to write files to specific directories in the file system path hierarchy. The attacker must:

1. Identify the unquoted service path through registry enumeration or service configuration queries
2. Determine a writable location within the path resolution sequence
3. Place a malicious executable at that location with a name that matches Windows' path resolution pattern
4. Wait for or trigger a service restart to execute the malicious payload with SYSTEM privileges

The attack does not require network access and can be performed by any local user with write permissions to relevant directories, making it particularly dangerous in shared or multi-user environments.

Detection Methods for CVE-2019-25275

Indicators of Compromise

• Unexpected executable files in root directories (e.g., C:\Program.exe, C:\Program Files.exe)
• Unusual process creation events from service contexts involving non-standard executables
• Registry modifications to the ImagePath value of BartVPNService
• Suspicious file write operations to C:\ or C:\Program Files\ directories

Detection Strategies

• Query Windows services for unquoted paths using PowerShell: Get-WmiObject win32_service | Where-Object {$_.PathName -notlike '"*"' -and $_.PathName -like '* *'}
• Monitor for creation of executables named Program.exe or similar variants in root or common installation directories
• Implement file integrity monitoring on system root directories
• Use endpoint detection tools to identify privilege escalation attempts via service manipulation

Monitoring Recommendations

• Enable Windows Security Event logging for service control manager events (Event IDs 7034, 7035, 7036, 7045)
• Monitor process creation events for unexpected parent-child relationships involving services
• Deploy SentinelOne Singularity platform to detect and block unauthorized privilege escalation attempts in real-time
• Implement periodic audits of service configurations to identify unquoted paths across the environment

How to Mitigate CVE-2019-25275

Immediate Actions Required

• Audit all installed services for unquoted path vulnerabilities using automated scripts or security tools
• Manually correct the BartVPNService registry entry by adding quotation marks around the ImagePath value
• Remove any suspicious executables from directories that could be targeted for path hijacking
• Restrict write permissions on system root directories and common installation paths
• Consider uninstalling BartVPN 1.2.2 if no vendor patch is available

Patch Information

No vendor patch information is currently available in the NVD. Organizations using BartVPN should contact the vendor directly for remediation guidance or consider alternative VPN solutions. Additional technical details can be found in the VulnCheck Advisory for BartVPN and Exploit-DB #47675.

Workarounds

• Manually quote the service path in the Windows registry under HKLM\SYSTEM\CurrentControlSet\Services\BartVPNService
• Use the sc config command to update the service binary path with proper quotation marks
• Implement application whitelisting to prevent execution of unauthorized binaries
• Deploy endpoint protection solutions capable of detecting service hijacking attempts

# Configuration example - Fix unquoted service path via registry
reg add "HKLM\SYSTEM\CurrentControlSet\Services\BartVPNService" /v ImagePath /t REG_EXPAND_SZ /d "\"C:\Program Files\BartVPN\BartVPNService.exe\"" /f

# Alternative using sc command (adjust path as needed)
sc config BartVPNService binPath= "\"C:\Program Files\BartVPN\BartVPNService.exe\""