CVE-2025-51089
📋 TL;DR
A heap-based buffer overflow vulnerability exists in Tenda AC8V4 routers via the /goform/GetParentControlInfo endpoint when manipulating the 'mac' argument. This allows attackers to potentially execute arbitrary code or crash the device. Users running Tenda AC8V4 routers with vulnerable firmware are affected.
💻 Affected Systems
- Tenda AC8V4 router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, persistence, and lateral movement to connected networks.
Likely Case
Device crash causing denial of service, potentially requiring physical reset.
If Mitigated
Limited to denial of service if exploit fails or memory protections are in place.
🎯 Exploit Status
Exploit requires authentication to access the /goform/ endpoint. Public proof-of-concept code exists in GitHub repository.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: http://tenda.com
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates. 2. Download latest firmware for AC8V4. 3. Log into router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable web management interface
allPrevent access to vulnerable endpoint by disabling remote web management
Restrict access to admin interface
allLimit admin interface access to specific IP addresses only
🧯 If You Can't Patch
- Isolate router on separate network segment with strict firewall rules
- Disable parental control feature if not needed
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or System ToolsCheck Version:
Login to router web interface and check System Status pageVerify Fix Applied:
Verify firmware version is newer than V16.03.34.06 after update📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts followed by requests to /goform/GetParentControlInfo
- Unusual large payloads in POST requests to router management interface
Network Indicators:
- Unusual traffic patterns to router management port (typically 80/443)
- Exploit attempts with oversized 'mac' parameter values
SIEM Query:
source="router_logs" AND (uri="/goform/GetParentControlInfo" OR (post_data CONTAINS "mac=" AND size>1000))