CVE-2024-26314

Executive Summary

CVE-2024-26314 is a critical privilege escalation vulnerability in Jungo WinDriver, affecting versions 6.0.0 through 16.1.0. The vulnerability stems from improper privilege management, allowing a local attacker to escalate privileges and execute arbitrary code. This flaw is particularly dangerous in environments where WinDriver is used to interface with hardware, as it can lead to full system compromise. No public proof-of-concept (PoC) or exploit code is currently available, and the vendor has not released a patch. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the risk remains high due to the potential impact.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a driver-level issue in Jungo WinDriver, a commercial software development kit (SDK) for Windows driver development. Organizations using WinDriver should treat this as a critical supply chain risk, as the SDK is often integrated into custom hardware solutions.

CVSS Breakdown & Threat Level

The CVSS score is listed as 0.0, but this is likely a placeholder. Based on the description (local privilege escalation to arbitrary code execution), a reasonable CVSS v3.1 vector would be:

• Attack Vector (AV): Local (L)
• Attack Complexity (AC): Low (L)
• Privileges Required (PR): Low (L)
• User Interaction (UI): None (N)
• Scope (S): Unchanged (U)
• Confidentiality (C): High (H)
• Integrity (I): High (H)
• Availability (A): High (H)

Estimated CVSS Score: 7.8 (High)

Threat Level: High. Local exploitation can lead to full system compromise, including kernel-level access.

Deep Dive & Mechanics

Jungo WinDriver is a toolkit that allows developers to create Windows device drivers without deep kernel knowledge. It operates by loading a kernel-mode driver (windrvr.sys) that provides user-mode applications with direct hardware access.

The vulnerability (CWE-269: Improper Privilege Management) likely exists in the IOCTL (Input/Output Control) handling within the WinDriver kernel driver. A local attacker with low privileges can send specially crafted IOCTL requests to the driver, causing it to:

1. Elevate the attacker's token to SYSTEM or kernel-level privileges.
2. Execute arbitrary code in kernel mode.

The attack vector is local, meaning the attacker must already have access to the system (e.g., via a compromised user account or malware). Once exploited, the attacker gains full control over the system, including the ability to install rootkits, bypass security software, and persist.

Vulnerable vs. Patched Code

Since no patch is available, a direct code comparison is not possible. However, based on the vulnerability type, the following is a hypothetical example of the vulnerable IOCTL handling:

Vulnerable Code (C pseudo-code):

NTSTATUS DriverDispatch(PDEVICE_OBJECT DeviceObject, PIRP Irp) {
    PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);
    ULONG ioControlCode = irpStack->Parameters.DeviceIoControl.IoControlCode;
    PVOID inputBuffer = Irp->AssociatedIrp.SystemBuffer;
    ULONG inputBufferLength = irpStack->Parameters.DeviceIoControl.InputBufferLength;

    switch (ioControlCode) {
        case IOCTL_ELEVATE_PRIVILEGES:
            // No privilege check - allows any user to call this
            if (inputBufferLength >= sizeof(TOKEN_ELEVATION_DATA)) {
                PTOKEN_ELEVATION_DATA data = (PTOKEN_ELEVATION_DATA)inputBuffer;
                // Directly modifies token without validation
                SeTokenSetPrivileges(data->TokenHandle, data->Privileges);
            }
            break;
        // ... other cases
    }
    return STATUS_SUCCESS;
}

Patched Code (Hypothetical):

NTSTATUS DriverDispatch(PDEVICE_OBJECT DeviceObject, PIRP Irp) {
    PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);
    ULONG ioControlCode = irpStack->Parameters.DeviceIoControl.IoControlCode;
    PVOID inputBuffer = Irp->AssociatedIrp.SystemBuffer;
    ULONG inputBufferLength = irpStack->Parameters.DeviceIoControl.InputBufferLength;

    // Check if the caller is running with administrative privileges
    if (!SeSinglePrivilegeCheck(SeTakeOwnershipPrivilege, ExGetPreviousMode())) {
        return STATUS_ACCESS_DENIED;
    }

    switch (ioControlCode) {
        case IOCTL_ELEVATE_PRIVILEGES:
            // Only allow if caller is already privileged
            if (inputBufferLength >= sizeof(TOKEN_ELEVATION_DATA)) {
                PTOKEN_ELEVATION_DATA data = (PTOKEN_ELEVATION_DATA)inputBuffer;
                // Additional validation
                if (data->TokenHandle != NULL) {
                    SeTokenSetPrivileges(data->TokenHandle, data->Privileges);
                }
            }
            break;
        // ... other cases
    }
    return STATUS_SUCCESS;
}

Exploitation & Lab Setup

Red Team

Objective: Escalate privileges from a low-privileged user to SYSTEM.

Prerequisites:

• Windows system with Jungo WinDriver 6.0.0 to 16.1.0 installed.
• Low-privileged user access (e.g., via phishing or initial foothold).
• Python or C compiler to craft IOCTL requests.

Exploitation Steps:

1. Identify the WinDriver device: Use WinObj or DeviceTree to find the WinDriver device object (e.g., \\.\WinDriver).
2. Craft IOCTL request: The vulnerable IOCTL code is likely undocumented. Use a tool like IOCTLDecoder or reverse engineer the driver to find the correct code.
3. Execute exploit: Send the IOCTL request to elevate privileges.

Example Python script (conceptual):

import ctypes
import win32file
import win32con

# Open handle to WinDriver device
handle = win32file.CreateFile(
    "\\\\.\\WinDriver",
    win32con.GENERIC_READ | win32con.GENERIC_WRITE,
    0,
    None,
    win32con.OPEN_EXISTING,
    0,
    None
)

# Craft IOCTL buffer (hypothetical)
buffer = ctypes.create_string_buffer(1024)
# Fill buffer with token elevation data
# ...

# Send IOCTL
win32file.DeviceIoControl(handle, 0x12345678, buffer, len(buffer), None, 0, None, None)

Expected Outcome: The attacker's process token is elevated to SYSTEM, allowing execution of arbitrary commands with highest privileges.

Blue Team

Detection:

• Monitor for unusual IOCTL calls to windrvr.sys from non-system processes.
• Use Sysmon to log process creation and driver events.
• Enable Windows Event Logging for kernel driver operations.

Hunting:

• Search for processes opening handles to \\.\WinDriver or \\.\windrvr.
• Look for unexpected privilege escalation events (Event ID 4672: Special Privilege Assigned to New Logon).

Mitigation:

• Restrict installation of WinDriver to trusted administrators only.
• Use AppLocker or WDAC to block unauthorized driver loading.
• Monitor for known vulnerable versions of WinDriver in the environment.

Indicators of Compromise (IOCs)

• File Hashes (SHA256): (None available, but monitor for windrvr.sys with version 6.0.0 to 16.1.0)
• Registry Keys: HKLM\SYSTEM\CurrentControlSet\Services\windrvr
• Network: No network indicators (local exploit).
• Process: windrvr.sys loaded into kernel space.
• Event Logs: Event ID 4672 (Special Privilege Assigned to New Logon) from unexpected users.

Detection Engineering

YARA Rule

rule CVE_2024_26314_WinDriver_EoP {
    meta:
        description = "Detects Jungo WinDriver vulnerable versions (6.0.0-16.1.0)"
        author = "Valters IT"
        date = "2025-04-10"
        hash = "unknown"
    strings:
        $s1 = "WinDriver" wide ascii nocase
        $s2 = "windrvr.sys" wide ascii nocase
        $v1 = { 36 2E 30 2E 30 } // "6.0.0"
        $v2 = { 31 36 2E 31 2E 30 } // "16.1.0"
    condition:
        ($s1 or $s2) and ($v1 or $v2)
}

Sigma Rule

title: CVE-2024-26314 - WinDriver Privilege Escalation
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects potential exploitation of CVE-2024-26314 via IOCTL calls to WinDriver
author: Valters IT
date: 2025-04-10
logsource:
    product: windows
    service: sysmon
detection:
    selection:
        EventID: 11  # FileCreate
        TargetFilename|contains: 'windrvr.sys'
    condition: selection
falsepositives:
    - Legitimate WinDriver installations
level: high

Suricata Rule

alert ip any any -> any any (msg:"CVE-2024-26314 - WinDriver Privilege Escalation Attempt"; content:"|00 00 00 00|"; depth:4; sid:1000001; rev:1;)

Note: Suricata rule is generic as this is a local exploit; network detection is not applicable.

Remediation & Mitigation

Immediate Actions:

1. Disable WinDriver: If not required, uninstall WinDriver or disable the windrvr service.
2. Restrict Access: Use Group Policy to prevent non-administrators from loading kernel drivers.
3. Monitor: Implement the detection rules above to identify exploitation attempts.

Long-term:

• Contact Jungo for a patch or upgrade to a version beyond 16.1.0 (if available).
• Consider migrating to alternative driver development frameworks (e.g., Microsoft WDF).
• Apply the principle of least privilege to all user accounts.

Workaround: If WinDriver is critical, run it in a virtualized environment or with strict driver signing policies.

Valters IT