CVE-2025-29363
📋 TL;DR
Tenda RX3 routers running vulnerable firmware are susceptible to a buffer overflow attack via the schedStartTime and schedEndTime parameters in the /goform/saveParentControlInfo endpoint. This allows attackers to cause Denial of Service (DoS) by sending specially crafted packets. Users with affected Tenda RX3 routers are at risk.
💻 Affected Systems
- Tenda RX3
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router crash requiring physical reboot, potential remote code execution if buffer overflow can be leveraged further (though not indicated in CVE description).
Likely Case
Router becomes unresponsive, requiring reboot to restore functionality, disrupting network connectivity for all connected devices.
If Mitigated
If properly segmented and firewalled, impact limited to internal network disruption rather than external compromise.
🎯 Exploit Status
Exploitation requires sending crafted HTTP POST requests to the vulnerable endpoint. No authentication bypass mentioned, but default credentials or exposed admin interface could lower barrier.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Tenda for firmware updates beyond V16.03.13.11
Vendor Advisory: Not provided in CVE references
Restart Required: Yes
Instructions:
1. Log into Tenda RX3 web interface. 2. Navigate to System Tools > Firmware Upgrade. 3. Download latest firmware from Tenda website. 4. Upload and apply firmware update. 5. Router will reboot automatically.
🔧 Temporary Workarounds
Disable Parent Control Feature
allRemove attack surface by disabling the vulnerable parent control functionality
Navigate to Parent Control settings in web interface and disable feature
Restrict Web Interface Access
allLimit access to router management interface to trusted IPs only
Configure firewall rules to restrict access to router IP on ports 80/443
🧯 If You Can't Patch
- Segment router on isolated network VLAN
- Implement network monitoring for abnormal HTTP POST requests to /goform/saveParentControlInfo
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System StatusCheck Version:
curl -s http://router-ip/goform/getStatus | grep versionVerify Fix Applied:
Confirm firmware version is newer than V16.03.13.11 and test parent control functionality📡 Detection & Monitoring
Log Indicators:
- Multiple HTTP POST requests to /goform/saveParentControlInfo with abnormal parameter lengths
- Router crash/reboot logs
Network Indicators:
- HTTP traffic to router IP with unusually long schedStartTime/schedEndTime parameters
- Sudden drop in router responsiveness
SIEM Query:
source="router_logs" AND uri="/goform/saveParentControlInfo" AND (param_length>100 OR status=500)