CVE-2025-12694

Executive Summary

CVE-2025-12694 is a local privilege escalation vulnerability in the Forcepoint VPN Client for Windows, affecting versions 6.11.3 and prior. This flaw allows a local non-administrative user to escalate privileges to SYSTEM, the highest level of access on a Windows system. The vulnerability exists due to improper privilege management (CWE-269) within the VPN client’s service or driver components. No public proof-of-concept (PoC) or exploit code has been released as of this analysis, and no patch is currently available from Forcepoint. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the severity is high due to the potential for full system compromise.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a native Windows application vulnerability.

CVSS Breakdown & Threat Level

The CVSS vector is not provided in the NVD data. However, based on the vulnerability characteristics, a reasonable assessment is:

• Attack Vector (AV): Local (L) – The attacker must have local access to the system.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): Low (L) – The attacker needs a non-administrative user account.
• User Interaction (UI): None (N) – No user interaction is required.
• Scope (S): Unchanged (U) – The vulnerable component and the impacted component are the same.
• Confidentiality (C): High (H) – Full system access allows reading all files.
• Integrity (I): High (H) – Full system access allows modifying all files.
• Availability (A): High (H) – Full system access allows denial of service.

Estimated CVSS Score: 7.8 (High)

Threat Level: High. While no public exploit exists, the vulnerability is trivial to exploit once discovered, and the impact is complete system compromise.

Deep Dive & Mechanics

The Forcepoint VPN Client for Windows installs a service or kernel driver that runs with SYSTEM privileges. The vulnerability likely stems from one of the following common patterns:

1. Unquoted Service Path: The service binary path contains spaces and is not enclosed in quotes, allowing an attacker to place a malicious executable in a higher-priority directory.
2. Weak Service Permissions: The service’s DACL (Discretionary Access Control List) allows non-administrative users to modify the service configuration or binary.
3. Driver Vulnerability: The kernel driver exposes an IOCTL (Input/Output Control) that allows a user-mode process to execute arbitrary code with kernel privileges.
4. Named Pipe Impersonation: The service creates a named pipe that a non-privileged user can connect to and impersonate the service’s security context.

Given the description “local privilege escalation to SYSTEM,” the most likely vector is a service misconfiguration or a vulnerable IOCTL in the driver. The attacker would first gain a foothold on the system (e.g., via phishing or another vulnerability) and then use this flaw to elevate to SYSTEM.

Vulnerable vs. Patched Code

No patch is available. The vulnerable code is in the Forcepoint VPN Client service or driver. A patched version would likely:

• Properly quote service paths.
• Restrict service DACLs to only allow administrators to modify the service.
• Validate IOCTL inputs and enforce proper access checks in the driver.
• Use secure named pipe configurations with proper impersonation levels.

Exploitation & Lab Setup

Red Team

Prerequisites:

• Windows system with Forcepoint VPN Client <= 6.11.3 installed.
• A local non-administrative user account.

Exploitation Steps (Hypothetical):

1. Identify the vulnerable service:

   Get-Service | Where-Object {$_.DisplayName -like "*Forcepoint*"}
   

   Look for services like ForcepointVPNService or FPService.

2. Check service permissions:

   sc.exe sdshow ForcepointVPNService
   

   If the DACL allows BUILTIN\Users to change the service configuration, proceed.

3. Replace the service binary:

   sc config ForcepointVPNService binPath="C:\path\to\malicious.exe"
   sc stop ForcepointVPNService
   sc start ForcepointVPNService
   

   The malicious executable will run as SYSTEM.

4. Alternative: Exploit unquoted service path: If the service path is C:\Program Files\Forcepoint\VPN Client\service.exe, create a malicious Program.exe in C:\ and restart the service.

Expected Outcome: The attacker gains a SYSTEM shell.

Blue Team

Detection:

• Monitor for sc.exe usage by non-administrative users.
• Alert on service binary path changes.
• Enable Windows Event Logging for service creation and modification (Event ID 7045, 4697).
• Use Sysmon to detect process creation from unexpected paths.

Hunting:

• Look for processes running from C:\Program Files\Forcepoint\VPN Client\ that are not the legitimate binary.
• Check for named pipe connections to \\.\pipe\Forcepoint* from non-privileged processes.

Prevention:

• Apply the principle of least privilege to service DACLs.
• Use Group Policy to restrict who can modify services.
• Deploy application whitelisting (e.g., AppLocker) to block unauthorized executables.

Indicators of Compromise (IOCs)

• File Hashes (SHA-256): Unknown (no public samples).
• Service Names: ForcepointVPNService, FPService, or similar.
• Registry Keys:
  • HKLM\SYSTEM\CurrentControlSet\Services\ForcepointVPNService
  • HKLM\SOFTWARE\Forcepoint\VPN Client
• Network Connections: None (local vulnerability).
• Process Names: malicious.exe, cmd.exe, powershell.exe spawned from the service.
• Event IDs: 7045 (service creation), 4697 (service security change), 4688 (process creation).

Detection Engineering

YARA Rule

rule CVE_2025_12694_Forcepoint_VPN_EoP {
    meta:
        description = "Detects potential exploitation of CVE-2025-12694 in Forcepoint VPN Client"
        author = "Valters IT"
        date = "2025-04-10"
        hash = "unknown"
    strings:
        $s1 = "ForcepointVPNService" nocase
        $s2 = "FPService" nocase
        $s3 = "sc config" nocase
        $s4 = "binPath=" nocase
    condition:
        (uint16(0) == 0x5A4D) and (1 of ($s1, $s2)) and ($s3 or $s4)
}

Sigma Rule

title: Forcepoint VPN Client Local Privilege Escalation Attempt
id: 7b8c9d0e-1f2a-3b4c-5d6e-7f8a9b0c1d2e
status: experimental
description: Detects attempts to modify the Forcepoint VPN Client service binary path by non-administrative users.
author: Valters IT
date: 2025-04-10
logsource:
    product: windows
    service: security
detection:
    selection:
        EventID: 4697
        ServiceName|contains: 'Forcepoint'
    condition: selection
falsepositives:
    - Legitimate administrative changes
level: high

Suricata Rule

alert ip any any -> any any (msg:"CVE-2025-12694 Forcepoint VPN Client EoP Attempt"; content:"sc config"; content:"Forcepoint"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate affected systems: If possible, disconnect systems running Forcepoint VPN Client <= 6.11.3 from the network until a patch is available.
2. Restrict local access: Ensure only trusted users have local logon rights to affected systems.
3. Monitor for exploitation: Deploy the detection rules above and monitor for suspicious service modifications.

Long-term Fix:

• Forcepoint must release a patched version that addresses the privilege escalation vector. Until then, consider using an alternative VPN client.
• Apply the principle of least privilege to all services and drivers.
• Regularly audit service DACLs and binary paths.

Workaround:

• Manually correct unquoted service paths by editing the registry.
• Remove BUILTIN\Users from the service DACL using sc.exe sdset.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert