CVE-2022-25561
📋 TL;DR
Tenda AX12 routers running firmware v22.03.01.21 contain a stack overflow vulnerability in the sub_42DE00 function. Attackers can exploit this via the list parameter to cause a Denial of Service (DoS), potentially crashing the device. This affects all users of Tenda AX12 routers with the vulnerable firmware version.
💻 Affected Systems
- Tenda AX12
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device crash requiring physical reboot, potentially leading to extended network downtime and service disruption.
Likely Case
Router becomes unresponsive, requiring reboot to restore functionality, causing temporary network outage.
If Mitigated
If properly segmented and monitored, impact limited to isolated network segment with quick recovery possible.
🎯 Exploit Status
Public GitHub repository contains vulnerability details and likely exploit code. DoS exploits typically require minimal sophistication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check Tenda support site for firmware updates. 2. Download latest firmware. 3. Log into router admin interface. 4. Navigate to firmware upgrade section. 5. Upload and apply new firmware. 6. Wait for router to reboot.
🔧 Temporary Workarounds
Disable remote administration
allPrevent external access to router management interface
Login to router admin → System Tools → Remote Management → Disable
Network segmentation
allIsolate router management interface to trusted network only
Configure firewall rules to restrict access to router IP on ports 80/443
🧯 If You Can't Patch
- Replace with different router model or firmware version
- Implement network monitoring for DoS attempts against router
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or Firmware Upgrade sectionCheck Version:
Login to router web interface and navigate to System Status pageVerify Fix Applied:
Verify firmware version is no longer v22.03.01.21 after update📡 Detection & Monitoring
Log Indicators:
- Router crash/reboot logs
- Unusual traffic patterns to router management interface
Network Indicators:
- Multiple malformed requests to router on port 80/443
- Sudden loss of router responsiveness
SIEM Query:
source="router_logs" AND (event="crash" OR event="reboot") OR dest_ip="router_ip" AND (uri CONTAINS "list" OR method="POST")