CVE-2022-27076
📋 TL;DR
CVE-2022-27076 is a command injection vulnerability in Tenda M3 routers that allows attackers to execute arbitrary commands on the device. This affects Tenda M3 router users running vulnerable firmware versions. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- Tenda M3 Router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router takeover, credential theft, network pivoting, and persistent backdoor installation.
Likely Case
Router compromise leading to DNS hijacking, traffic interception, and network disruption.
If Mitigated
Limited impact if device is isolated behind firewall with no external access.
🎯 Exploit Status
Exploit requires authentication to the router's web interface. Public proof-of-concept code is available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Tenda website for latest firmware
Vendor Advisory: Not publicly documented by vendor
Restart Required: Yes
Instructions:
1. Log into Tenda router web interface. 2. Navigate to System Tools > Firmware Upgrade. 3. Download latest firmware from Tenda website. 4. Upload and install firmware. 5. Reboot router.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router web interface
Network Segmentation
allIsolate router management interface to trusted network
🧯 If You Can't Patch
- Change default admin credentials to strong passwords
- Disable WAN access to router management interface
🔍 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:
Verify firmware version is newer than 1.10 V1.0.0.12(4856)📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/delAd
- Suspicious command execution in router logs
Network Indicators:
- Unexpected outbound connections from router
- Traffic to suspicious IPs
SIEM Query:
source="router" AND (uri="/goform/delAd" OR command="*;*" OR command="*|*")