CVE-2025-29359
📋 TL;DR
Tenda RX3 routers running specific firmware versions contain a buffer overflow vulnerability in the deviceId parameter of the saveParentControlInfo endpoint. Attackers can exploit this to cause denial of service by sending specially crafted packets. This affects all users of vulnerable Tenda RX3 router configurations.
💻 Affected Systems
- Tenda RX3 router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router crash requiring physical reboot, potentially allowing remote code execution if the overflow can be controlled precisely.
Likely Case
Router becomes unresponsive or reboots, disrupting network connectivity for all connected devices.
If Mitigated
Limited impact if the router is behind a firewall with restricted access to its management interface.
🎯 Exploit Status
Exploitation requires sending crafted HTTP requests to the router's management interface. The PDF reference suggests technical details are available but not a full public exploit.
🛠️ 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 Tenda RX3 router web interface. 2. Navigate to System Tools > Firmware Upgrade. 3. Download latest firmware from Tenda website. 4. Upload and install the update. 5. Reboot the router after installation.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to the router's web interface
Restrict access to management interface
allUse firewall rules to limit which IP addresses can access the router's admin panel
🧯 If You Can't Patch
- Place router behind a firewall that blocks all inbound access to port 80/443
- Disable parental control feature if not needed
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface under System StatusCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Confirm firmware version is updated beyond V16.03.13.11📡 Detection & Monitoring
Log Indicators:
- Multiple failed HTTP POST requests to /goform/saveParentControlInfo with long deviceId parameters
- Router reboot events in system logs
Network Indicators:
- Unusual HTTP traffic to router management port with oversized parameters
SIEM Query:
source="router_logs" AND (uri="/goform/saveParentControlInfo" AND deviceId.length>100) OR event="system_reboot"