CVE-2025-47415

Executive Summary

CVE-2025-47415 is a path traversal vulnerability affecting Crestron touchscreen devices, specifically the x70 series (TSW-760, TSW-1060) and potentially other models. The vulnerability allows an unauthenticated attacker to perform relative path traversal, potentially reading arbitrary files from the device’s filesystem. This could expose sensitive configuration data, credentials, or other proprietary information. The x70 series has a fixed firmware version (3.001.0031.001), while the TSW-760 and TSW-1060 are discontinued and remain unpatched. No public proof-of-concept (PoC) or exploit code has been released at this time.

Supply Chain & Package Security

This vulnerability is not related to any open-source package manager (NPM, PyPI, Go, Ruby). It is a firmware-level issue in proprietary Crestron hardware.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (NVD base score not yet assigned; estimated based on vector)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: None
• Availability Impact: None
• Threat Level: High (due to ease of exploitation and potential for sensitive data exposure)

Deep Dive & Mechanics

The vulnerability is a classic path traversal (CWE-22) in the Crestron touchscreen web interface or API. The device fails to properly sanitize user-supplied input when constructing file paths. By injecting ../ sequences, an attacker can escape the intended web root directory and access arbitrary files on the device’s filesystem.

Attack Scenario:

1. An attacker sends a crafted HTTP request to the touchscreen’s web server, e.g., GET /../../../etc/passwd.
2. The server processes the path without validation, returning the contents of /etc/passwd.
3. The attacker can then enumerate other files, such as configuration files containing network credentials, SSH keys, or proprietary Crestron settings.

Affected Endpoints:

• Likely any endpoint that serves static files or handles file downloads/uploads.
• The vulnerability is present in firmware versions prior to 3.001.0031.001 for x70 series, and in version 3.002.1061 for TSW-760/1060 (discontinued).

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# Example of vulnerable path handling
def get_file(request):
    filename = request.GET.get('file')
    # No sanitization
    filepath = "/var/www/html/" + filename
    with open(filepath, 'r') as f:
        return f.read()

Patched Code (Conceptual):

import os

def get_file(request):
    filename = request.GET.get('file')
    # Sanitize: remove path traversal sequences
    safe_filename = os.path.basename(filename)
    filepath = os.path.join("/var/www/html/", safe_filename)
    # Ensure the resolved path is within the allowed directory
    real_path = os.path.realpath(filepath)
    if not real_path.startswith("/var/www/html/"):
        return "Access denied", 403
    with open(real_path, 'r') as f:
        return f.read()

The patched version uses os.path.basename to strip directory components and then verifies the resolved path is within the intended directory.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

• Target: Crestron TSW-760 with firmware 3.002.1061 (or x70 with vulnerable firmware)
• Attacker: Kali Linux with curl or Burp Suite

Exploitation Steps:

1. Identify the target IP address (e.g., via Shodan or network scan).
2. Send a path traversal request:

   curl "http://<target_ip>/../../../etc/passwd"
   

3. If successful, the response will contain the contents of /etc/passwd.
4. Enumerate other files:

   curl "http://<target_ip>/../../../etc/shadow"
   curl "http://<target_ip>/../../../mnt/flash/config.cfg"
   

Note: No public exploit code is available. The above is a generic example.

Blue Team (Defensive)

Detection:

• Monitor web server logs for requests containing ../ or %2e%2e%2f (URL-encoded path traversal).
• Alert on any access to files outside the web root (e.g., /etc/passwd, /etc/shadow).

Mitigation:

• For x70 series: Upgrade to firmware 3.001.0031.001.
• For TSW-760/1060: Replace with supported hardware or isolate on a separate VLAN with strict access controls.
• Implement a Web Application Firewall (WAF) to block path traversal patterns.
• Disable unnecessary web services on the touchscreen.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests containing ../ or %2e%2e%2f in the URI.
  • Outbound connections from the touchscreen to unknown IPs (if data exfiltration occurs).
• File System IOCs:
  • Unauthorized access to /etc/passwd, /etc/shadow, /mnt/flash/config.cfg, or other sensitive files.
• Log IOCs:
  • Web server logs showing 200 responses to path traversal attempts.

Detection Engineering

YARA Rule

rule CVE_2025_47415_Path_Traversal {
    meta:
        description = "Detects path traversal attempts against Crestron touchscreens"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-47415"
    strings:
        $traversal1 = "../"
        $traversal2 = "..\\"
        $traversal3 = "%2e%2e%2f"
        $traversal4 = "%2e%2e%5c"
        $sensitive1 = "/etc/passwd"
        $sensitive2 = "/etc/shadow"
        $sensitive3 = "/mnt/flash/"
    condition:
        any of ($traversal*) and any of ($sensitive*)
}

Sigma Rule

title: CVE-2025-47415 Path Traversal on Crestron Touchscreen
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects path traversal attempts targeting Crestron touchscreen devices
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
        cs-uri-query|contains:
            - '/etc/passwd'
            - '/etc/shadow'
            - '/mnt/flash/'
    condition: selection
falsepositives:
    - Legitimate use of relative paths in some applications (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-47415 Path Traversal Attempt on Crestron Touchscreen"; flow:to_server,established; content:"../"; http_uri; content:"/etc/passwd"; http_uri; distance:0; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action:

   • For x70 series: Upgrade to firmware version 3.001.0031.001 or later.
   • For TSW-760 and TSW-1060: These devices are discontinued and will not receive a patch. Replace them with supported models or isolate them on a separate network segment with strict firewall rules.

2. Compensating Controls:

   • Deploy a WAF to block path traversal patterns.
   • Restrict network access to the touchscreen’s web interface to trusted IPs only.
   • Disable the web server if not required.

3. Long-Term:

   • Implement a vulnerability management program to track and patch Crestron devices.
   • Consider replacing end-of-life hardware with supported alternatives.

Valters IT
Securing Your Digital Frontier