CVE-2025-29362
📋 TL;DR
This buffer overflow vulnerability in Tenda RX3 routers allows attackers to cause denial of service by sending specially crafted packets to the web interface. It affects users running vulnerable firmware versions on Tenda RX3 devices. The vulnerability is in the web management interface's form handling code.
💻 Affected Systems
- Tenda RX3 router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router crash requiring physical reset, potentially disrupting all network connectivity for connected devices.
Likely Case
Router becomes unresponsive, requiring reboot to restore functionality, causing temporary network outage.
If Mitigated
Limited impact if router is behind firewall with restricted web interface access.
🎯 Exploit Status
Requires sending crafted HTTP POST request to specific endpoint. No authentication bypass mentioned.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Tenda for firmware updates beyond V16.03.13.11
Vendor Advisory: Not provided in references
Restart Required: Yes
Instructions:
1. Log into router web interface. 2. Navigate to firmware update section. 3. Download latest firmware from Tenda website. 4. Upload and apply firmware update. 5. Reboot router after update completes.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to router web interface
Log into router admin panel and disable 'Remote Management' or 'Web Access from WAN'
Restrict web interface access
allLimit which IPs can access router management interface
Configure firewall rules to only allow trusted IPs to access router web interface (typically port 80/443)
🧯 If You Can't Patch
- Segment network to isolate router management interface
- Implement network monitoring for abnormal HTTP requests to /goform/setPptpUserList
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface under System Status or About pageCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Verify firmware version is newer than V16.03.13.11 after update📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /goform/setPptpUserList with abnormal payloads
- Router crash/reboot logs
Network Indicators:
- HTTP POST requests to /goform/setPptpUserList with unusually long 'list' parameter
SIEM Query:
http.method:POST AND http.uri:"/goform/setPptpUserList" AND http.request_body_length > 1000