CVE-2025-25430
📋 TL;DR
This CVE describes a stored cross-site scripting (XSS) vulnerability in Trendnet TEW-929DRU routers. Attackers can inject malicious scripts via the configname parameter on the /cbi_addcert.htm page, which are then executed when legitimate users view the affected page. This affects administrators and users who access the router's web interface.
💻 Affected Systems
- Trendnet TEW-929DRU
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker could steal administrator credentials, hijack sessions, redirect users to malicious sites, or perform actions on behalf of authenticated users, potentially leading to full router compromise.
Likely Case
Attackers with access to the router's web interface could inject malicious scripts that execute when administrators view certificate configuration pages, potentially stealing session cookies or performing limited unauthorized actions.
If Mitigated
With proper input validation and output encoding, the malicious scripts would be rendered harmless as text rather than executable code.
🎯 Exploit Status
Exploitation requires access to the router's web interface and ability to modify certificate configuration names. The provided references contain technical details about the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
1. Check Trendnet's official website for firmware updates. 2. Download the latest firmware for TEW-929DRU. 3. Log into router web interface. 4. Navigate to Administration > Firmware Upgrade. 5. Upload and apply the new firmware.
🔧 Temporary Workarounds
Disable WAN access to web interface
allPrevent external access to the vulnerable web interface by disabling remote management
Log into router > Advanced > Remote Management > Disable
Implement network segmentation
allRestrict access to router management interface to trusted networks only
🧯 If You Can't Patch
- Restrict access to router management interface to trusted IP addresses only
- Implement web application firewall (WAF) rules to block XSS payloads targeting the configname parameter
🔍 How to Verify
Check if Vulnerable:
Access the router web interface, navigate to /cbi_addcert.htm, and attempt to inject a simple XSS payload like <script>alert('test')</script> in the configname parameter.Check Version:
Log into router web interface and check firmware version on status page or via command: curl -s http://router-ip/status.cgi | grep firmwareVerify Fix Applied:
After applying any firmware update, repeat the vulnerability check to confirm the payload is properly sanitized and does not execute.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cbi_addcert.htm with script tags in parameters
- Multiple failed login attempts followed by configuration changes
Network Indicators:
- HTTP requests containing script tags or JavaScript in configname parameter
- Unusual outbound connections from router after configuration changes
SIEM Query:
source="router_logs" AND (uri_path="/cbi_addcert.htm" AND (param="configname" AND value CONTAINS "<script>" OR value CONTAINS "javascript:"))