CVE-2025-64054
📋 TL;DR
A reflected Cross-Site Scripting (XSS) vulnerability in Fanvil x210 VoIP phones running firmware version 2.12.20 allows attackers to inject malicious scripts via crafted POST requests to the /cgi-bin/webconfig?page=upload&action=submit endpoint. This could enable denial of service attacks or potentially arbitrary command execution. Organizations using these specific Fanvil devices are affected.
💻 Affected Systems
- Fanvil x210 VoIP Phone
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could execute arbitrary commands on the device, potentially gaining full control, disrupting phone services, or using the device as a pivot point into the network.
Likely Case
Attackers would typically achieve denial of service by crashing the web interface or executing limited malicious scripts in the context of an authenticated administrator's session.
If Mitigated
With proper network segmentation and access controls, impact would be limited to the specific device's web interface functionality.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated users into interacting with malicious content. The GitHub advisory contains technical details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: http://fanvil.com
Restart Required: No
Instructions:
1. Check Fanvil's official website for security advisories. 2. If a patch is released, download the firmware update. 3. Upload the firmware to affected devices via the web interface. 4. Reboot devices after update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate Fanvil x210 devices from untrusted networks and restrict access to the web configuration interface.
Access Control Lists
allImplement firewall rules to only allow trusted IP addresses to access the device's web interface (typically port 80/443).
🧯 If You Can't Patch
- Disable the web configuration interface if not required for operations
- Implement strict Content Security Policy (CSP) headers if supported by the device firmware
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via web interface: Login > System > Status > Firmware Version. If version is 2.12.20, device is vulnerable.Check Version:
curl -s http://[device-ip]/cgi-bin/webconfig?page=status | grep -i firmwareVerify Fix Applied:
After applying any vendor patch, verify firmware version is no longer 2.12.20 and test the /cgi-bin/webconfig endpoint with safe XSS payloads.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/webconfig?page=upload&action=submit containing script tags or JavaScript code
- Multiple failed authentication attempts followed by successful access to configuration pages
Network Indicators:
- HTTP requests with suspicious parameters containing <script>, javascript:, or encoded payloads directed at Fanvil x210 devices
SIEM Query:
source="firewall" AND dest_ip="[fanvil-device-ip]" AND url="*cgi-bin/webconfig*" AND (http_method="POST" OR params="*script*" OR params="*javascript:*")