CVE-2025-1898
📋 TL;DR
A critical buffer overflow vulnerability in Tenda TX3 routers allows remote attackers to execute arbitrary code by manipulating the schedStartTime/schedEndTime parameters in the /goform/openSchedWifi endpoint. This affects Tenda TX3 routers running firmware version 16.03.13.11_multi. Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Tenda TX3 router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, creation of persistent backdoors, lateral movement to internal networks, and botnet recruitment.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept network traffic, or use the device as a pivot point for further attacks.
If Mitigated
Denial of service or limited information disclosure if exploit fails or is partially mitigated by network controls.
🎯 Exploit Status
Public exploit details are available in the GitHub repository, making exploitation straightforward for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.tenda.com.cn/
Restart Required: Yes
Instructions:
1. Check Tenda's official website for firmware updates. 2. Download the latest firmware for TX3. 3. Log into router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install the new firmware. 6. Reboot the router.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to the vulnerable endpoint by disabling remote administration features.
Network segmentation
allIsolate TX3 routers in a separate VLAN with strict firewall rules blocking access to management interfaces.
🧯 If You Can't Patch
- Replace affected Tenda TX3 routers with different models or brands that are not vulnerable.
- Implement strict network access controls to block all traffic to the router's management interface from untrusted networks.
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or System Tools. If version is 16.03.13.11_multi, the device is vulnerable.Check Version:
Log into router web interface and navigate to System Status page, or check via SSH if enabled (not recommended due to vulnerability).Verify Fix Applied:
After updating firmware, verify the version has changed from 16.03.13.11_multi to a newer version.📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /goform/openSchedWifi with unusually long schedStartTime/schedEndTime parameters
- Router crash/reboot logs
- Unusual process execution in router logs
Network Indicators:
- HTTP POST requests to router IP on port 80/443 targeting /goform/openSchedWifi with buffer overflow patterns in parameters
- Sudden changes in router configuration or network behavior
SIEM Query:
source="router_logs" AND (url="/goform/openSchedWifi" AND (param_length>100 OR contains(param,"schedStartTime") OR contains(param,"schedEndTime")))