CVE-2017-8220
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary commands on TP-Link C2 and C20i devices by sending specially crafted HTTP POST requests containing shell commands in the 'host=' parameter. This affects all users of these devices with vulnerable firmware versions, potentially giving attackers full control over the device.
💻 Affected Systems
- TP-Link C2
- TP-Link C20i
📦 What is this software?
C2 Firmware by Tp Link
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover allowing installation of persistent malware, network pivoting, data theft, and participation in botnets.
Likely Case
Device compromise leading to credential theft, network surveillance, and use as attack platform.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Single HTTP request with shell commands in POST data is sufficient for exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware versions after 0.9.1 4.2 v0032.0 Build 160706 Rel.37961n
Vendor Advisory: https://www.tp-link.com/us/support/download/c2/#Firmware
Restart Required: Yes
Instructions:
1. Download latest firmware from TP-Link website. 2. Log into device web interface. 3. Navigate to System Tools > Firmware Upgrade. 4. Upload firmware file. 5. Wait for automatic reboot.
🔧 Temporary Workarounds
Network Access Control
allBlock external access to device management interface
Firewall Rules
allRestrict HTTP/HTTPS access to device from trusted networks only
🧯 If You Can't Patch
- Isolate affected devices in separate VLAN with strict access controls
- Implement network monitoring for suspicious HTTP requests to device management interface
🔍 How to Verify
Check if Vulnerable:
Check firmware version in device web interface under System Tools > Firmware UpgradeCheck Version:
curl -s http://device-ip/ | grep -i firmwareVerify Fix Applied:
Verify firmware version is newer than 0.9.1 4.2 v0032.0 Build 160706 Rel.37961n📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests with shell commands in 'host=' parameter
- Unusual process execution from web service
Network Indicators:
- HTTP requests to device management interface with command injection patterns
- Outbound connections from device to suspicious IPs
SIEM Query:
source="device_logs" AND ("host=" AND ("bash" OR "sh" OR "cmd" OR "powershell"))